initialization vs assignment

Given the folowing class

class Ctest{
public:
Ctest( int i, int j) :a(i) { b = j; }
private:
int a, b;
}

When creating an object of type Ctest, what advantage is there to setting
the member variables a and b using initialization, :a(i), as opposed to
using assignment, b = j.

-charles

"Charles Stapleton" <cStapleton@no.junk> wrote...[color=blue]
> Given the folowing class
>
> class Ctest{
> public:
> Ctest( int i, int j) :a(i) { b = j; }
> private:
> int a, b;
> }
>
> When creating an object of type Ctest, what advantage is there to setting
> the member variables a and b using initialization, :a(i), as opposed to
> using assignment, b = j.[/color]

This is answered in the FAQ Lite (you can find it if you follow the
link http://www.parashift.com/c++-faq-lite/). Please read the FAQ
before posting.

Victor

Charles Stapleton wrote:[color=blue]
> Given the folowing class
>
> class Ctest{
> public:
> Ctest( int i, int j) :a(i) { b = j; }
> private:
> int a, b;
> }
>
> When creating an object of type Ctest, what advantage is there to
> setting the member variables a and b using initialization, :a(i), as
> opposed to using assignment, b = j.
>
> -charles[/color]

IMHO, nothing, but when you have a variable of a class with no default
constructor, initialization is required.

- Pete

* Leor Zolman <leor@bdsoft.com> schriebt:[color=blue]
> On Sat, 03 Apr 2004 19:39:13 GMT, "Charles Stapleton" <cStapleton@no.junk>
> wrote:
>[color=green]
> >Given the folowing class
> >
> >class Ctest{
> > public:
> > Ctest( int i, int j) :a(i) { b = j; }
> > private:
> > int a, b;
> >}
> >
> >When creating an object of type Ctest, what advantage is there to setting
> >the member variables a and b using initialization, :a(i), as opposed to
> >using assignment, b = j.[/color]
>
> For non-const primitive types and references (though there are some good
> reasons to avoid const members or refs as data members), the only advantage
> is stylistic. If you happen to have a /mixture/ of primitive and class-type
> data members (along with base classes, perhaps), then all the
> initializations can be shown in the same place and in a uniform style.
>
> For any type with constructors, though, omitting the member (or base)
> initialization forces invocation of that class's default constructor before
> the body of the constructor is entered. If you then do an assignment in the
> body of your constructor (assuming assignment is even supported for that
> type), you'll be doing "extra work". If there's no default constructor, it
> won't compile (probably the better scenario, since you find out sooner that
> you've got some kind of a problem).[/color]

For answers like these I think it's a good idea to refer to the FAQ.

FAQ: <url: http://www.parashift.com/c++-faq-lite/ctors.html#faq-10.6>.

Unfortunately the FAQ does not mention the single most common "good" reason
to use assignment, namely, presence of initialization order dependencies.
Which should be designed away if possible, but that is sometimes impractical.
As a rule, if assignment is used instead of initialization list then either
there is an initialization order dependency or a newbie or both.

--
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail?

On Sat, 03 Apr 2004 19:39:13 GMT, "Charles Stapleton" <cStapleton@no.junk>
wrote:
[color=blue]
>Given the folowing class
>
>class Ctest{
> public:
> Ctest( int i, int j) :a(i) { b = j; }
> private:
> int a, b;
>}
>
>When creating an object of type Ctest, what advantage is there to setting
>the member variables a and b using initialization, :a(i), as opposed to
>using assignment, b = j.[/color]

For non-const primitive types and references (though there are some good
reasons to avoid const members or refs as data members), the only advantage
is stylistic. If you happen to have a /mixture/ of primitive and class-type
data members (along with base classes, perhaps), then all the
initializations can be shown in the same place and in a uniform style.

For any type with constructors, though, omitting the member (or base)
initialization forces invocation of that class's default constructor before
the body of the constructor is entered. If you then do an assignment in the
body of your constructor (assuming assignment is even supported for that
type), you'll be doing "extra work". If there's no default constructor, it
won't compile (probably the better scenario, since you find out sooner that
you've got some kind of a problem).
-leor
[color=blue]
>
>-charles
>[/color]

--
Leor Zolman --- BD Software --- www.bdsoft.com
On-Site Training in C/C++, Java, Perl and Unix
C++ users: Download BD Software's free STL Error Message Decryptor at:
www.bdsoft.com/tools/stlfilt.html

Victor Bazarov wrote:
[color=blue]
> "Charles Stapleton" <cStapleton@no.junk> wrote...[color=green]
>> Given the folowing class
>>
>> class Ctest{
>> public:
>> Ctest( int i, int j) :a(i) { b = j; }
>> private:
>> int a, b;
>> }
>>
>> When creating an object of type Ctest, what advantage is there to setting
>> the member variables a and b using initialization, :a(i), as opposed to
>> using assignment, b = j.[/color]
>
> This is answered in the FAQ Lite (you can find it if you follow the
> link http://www.parashift.com/c++-faq-lite/). Please read the FAQ
> before posting.
>
> Victor[/color]
Why?
--
p->m == (*p).m == p[0].m
http://www.kdevelop.org
http://www.suse.com
http://www.mozilla.org

* Leor Zolman <leor@bdsoft.com> schriebt:[color=blue]
> On Sat, 03 Apr 2004 19:39:13 GMT, "Charles Stapleton" <cStapleton@no.junk>
> wrote:
>[color=green]
> >Given the folowing class
> >
> >class Ctest{
> > public:
> > Ctest( int i, int j) :a(i) { b = j; }
> > private:
> > int a, b;
> >}
> >
> >When creating an object of type Ctest, what advantage is there to setting
> >the member variables a and b using initialization, :a(i), as opposed to
> >using assignment, b = j.[/color]
>
> For non-const primitive types and references (though there are some good
> reasons to avoid const members or refs as data members), the only advantage
> is stylistic. If you happen to have a /mixture/ of primitive and class-type
> data members (along with base classes, perhaps), then all the
> initializations can be shown in the same place and in a uniform style.
>
> For any type with constructors, though, omitting the member (or base)
> initialization forces invocation of that class's default constructor before
> the body of the constructor is entered. If you then do an assignment in the
> body of your constructor (assuming assignment is even supported for that
> type), you'll be doing "extra work". If there's no default constructor, it
> won't compile (probably the better scenario, since you find out sooner that
> you've got some kind of a problem).[/color]

For answers like these I think it's a good idea to refer to the FAQ.

FAQ: <url: http://www.parashift.com/c++-faq-lite/ctors.html#faq-10.6>.

Unfortunately the FAQ does not mention the single most common "good" reason
to use assignment, namely, presence of initialization order dependencies.
Which should be designed away if possible, but that is sometimes impractical.
As a rule, if assignment is used instead of initialization list then either
there is an initialization order dependency or a newbie or both.

--
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail?

"Steven T. Hatton" <susudata@setidava.kushan.aa> wrote...[color=blue]
> Victor Bazarov wrote:
>[color=green]
> > "Charles Stapleton" <cStapleton@no.junk> wrote...[color=darkred]
> >> Given the folowing class
> >>
> >> class Ctest{
> >> public:
> >> Ctest( int i, int j) :a(i) { b = j; }
> >> private:
> >> int a, b;
> >> }
> >>
> >> When creating an object of type Ctest, what advantage is there to[/color][/color][/color]
setting[color=blue][color=green][color=darkred]
> >> the member variables a and b using initialization, :a(i), as opposed to
> >> using assignment, b = j.[/color]
> >
> > This is answered in the FAQ Lite (you can find it if you follow the
> > link http://www.parashift.com/c++-faq-lite/). Please read the FAQ
> > before posting.
> >
> > Victor[/color]
> Why?[/color]
Because

Victor Bazarov wrote:
[color=blue]
> "Charles Stapleton" <cStapleton@no.junk> wrote...[color=green]
>> Given the folowing class
>>
>> class Ctest{
>> public:
>> Ctest( int i, int j) :a(i) { b = j; }
>> private:
>> int a, b;
>> }
>>
>> When creating an object of type Ctest, what advantage is there to setting
>> the member variables a and b using initialization, :a(i), as opposed to
>> using assignment, b = j.[/color]
>
> This is answered in the FAQ Lite (you can find it if you follow the
> link http://www.parashift.com/c++-faq-lite/). Please read the FAQ
> before posting.
>
> Victor[/color]
Why?
--
p->m == (*p).m == p[0].m
http://www.kdevelop.org
http://www.suse.com
http://www.mozilla.org

Victor Bazarov wrote:
[color=blue]
> "Steven T. Hatton" <susudata@setidava.kushan.aa> wrote...[color=green]
>> Victor Bazarov wrote:
>>[color=darkred]
>> > "Charles Stapleton" <cStapleton@no.junk> wrote...
>> >> Given the folowing class
>> >>
>> >> class Ctest{
>> >> public:
>> >> Ctest( int i, int j) :a(i) { b = j; }
>> >> private:
>> >> int a, b;
>> >> }
>> >>
>> >> When creating an object of type Ctest, what advantage is there to[/color][/color]
> setting[color=green][color=darkred]
>> >> the member variables a and b using initialization, :a(i), as opposed
>> >> to using assignment, b = j.
>> >
>> > This is answered in the FAQ Lite (you can find it if you follow the
>> > link http://www.parashift.com/c++-faq-lite/). Please read the FAQ
>> > before posting.
>> >
>> > Victor[/color]
>> Why?[/color]
> Because[/color]

It seems to me 'Please read the FAQ before posting' could be taken as
'Please RTFFAQ'.
--
p->m == (*p).m == p[0].m
http://www.kdevelop.org
http://www.suse.com
http://www.mozilla.org

* "Steven T. Hatton" <susudata@setidava.kushan.aa> schriebt:[color=blue]
>
> It seems to me 'Please read the FAQ before posting' could be taken as
> 'Please RTFFAQ'.[/color]

Just spell it out: Read The Fucking Manual.

With prudish & easily offended Americans (who, without noticing any of it,
offend all others not by their choice of words but by their actions) all over
the net, however, it is perhaps best not asserted in that form.

It's a mystery to me how MIT could set up the RTFM site in the first place,
but then MIT has not only the best & brightest of the US population, but also
many bright people from the rest of the world. I am quite sure that in
current Norway, striving to be more American than the Americans, something
like the RTFM could never have been set up. But then we no longer have any
technical educational institutions left in Norway -- the miniature MIT
called NTH was, a few years ago, subsumed by a humanities oriented university.

--
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail?

"Steven T. Hatton" <susudata@setidava.kushan.aa> wrote...[color=blue]
> Victor Bazarov wrote:
>[color=green]
> > "Charles Stapleton" <cStapleton@no.junk> wrote...[color=darkred]
> >> Given the folowing class
> >>
> >> class Ctest{
> >> public:
> >> Ctest( int i, int j) :a(i) { b = j; }
> >> private:
> >> int a, b;
> >> }
> >>
> >> When creating an object of type Ctest, what advantage is there to[/color][/color][/color]
setting[color=blue][color=green][color=darkred]
> >> the member variables a and b using initialization, :a(i), as opposed to
> >> using assignment, b = j.[/color]
> >
> > This is answered in the FAQ Lite (you can find it if you follow the
> > link http://www.parashift.com/c++-faq-lite/). Please read the FAQ
> > before posting.
> >
> > Victor[/color]
> Why?[/color]
Because

Victor Bazarov wrote:
[color=blue]
> "Steven T. Hatton" <susudata@setidava.kushan.aa> wrote...[color=green]
>> Victor Bazarov wrote:
>>[color=darkred]
>> > "Charles Stapleton" <cStapleton@no.junk> wrote...
>> >> Given the folowing class
>> >>
>> >> class Ctest{
>> >> public:
>> >> Ctest( int i, int j) :a(i) { b = j; }
>> >> private:
>> >> int a, b;
>> >> }
>> >>
>> >> When creating an object of type Ctest, what advantage is there to[/color][/color]
> setting[color=green][color=darkred]
>> >> the member variables a and b using initialization, :a(i), as opposed
>> >> to using assignment, b = j.
>> >
>> > This is answered in the FAQ Lite (you can find it if you follow the
>> > link http://www.parashift.com/c++-faq-lite/). Please read the FAQ
>> > before posting.
>> >
>> > Victor[/color]
>> Why?[/color]
> Because[/color]

It seems to me 'Please read the FAQ before posting' could be taken as
'Please RTFFAQ'.
--
p->m == (*p).m == p[0].m
http://www.kdevelop.org
http://www.suse.com
http://www.mozilla.org

* "Steven T. Hatton" <susudata@setidava.kushan.aa> schriebt:[color=blue]
>
> It seems to me 'Please read the FAQ before posting' could be taken as
> 'Please RTFFAQ'.[/color]

Just spell it out: Read The Fucking Manual.

With prudish & easily offended Americans (who, without noticing any of it,
offend all others not by their choice of words but by their actions) all over
the net, however, it is perhaps best not asserted in that form.

It's a mystery to me how MIT could set up the RTFM site in the first place,
but then MIT has not only the best & brightest of the US population, but also
many bright people from the rest of the world. I am quite sure that in
current Norway, striving to be more American than the Americans, something
like the RTFM could never have been set up. But then we no longer have any
technical educational institutions left in Norway -- the miniature MIT
called NTH was, a few years ago, subsumed by a humanities oriented university.

--
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail?

"Steven T. Hatton" <susudata@setidava.kushan.aa> wrote...[color=blue]
> Victor Bazarov wrote:
>[color=green]
> > "Steven T. Hatton" <susudata@setidava.kushan.aa> wrote...[color=darkred]
> >> Victor Bazarov wrote:
> >>
> >> > "Charles Stapleton" <cStapleton@no.junk> wrote...
> >> >> Given the folowing class
> >> >>
> >> >> class Ctest{
> >> >> public:
> >> >> Ctest( int i, int j) :a(i) { b = j; }
> >> >> private:
> >> >> int a, b;
> >> >> }
> >> >>
> >> >> When creating an object of type Ctest, what advantage is there to[/color]
> > setting[color=darkred]
> >> >> the member variables a and b using initialization, :a(i), as opposed
> >> >> to using assignment, b = j.
> >> >
> >> > This is answered in the FAQ Lite (you can find it if you follow the
> >> > link http://www.parashift.com/c++-faq-lite/). Please read the FAQ
> >> > before posting.
> >> >
> >> > Victor
> >> Why?[/color]
> > Because[/color]
>
> It seems to me 'Please read the FAQ before posting' could be taken as
> 'Please RTFFAQ'.[/color]

It could just as well be taken at its face value. What's your F point?

"Steven T. Hatton" <susudata@setidava.kushan.aa> wrote...[color=blue]
> Victor Bazarov wrote:
>[color=green]
> > "Steven T. Hatton" <susudata@setidava.kushan.aa> wrote...[color=darkred]
> >> Victor Bazarov wrote:
> >>
> >> > "Charles Stapleton" <cStapleton@no.junk> wrote...
> >> >> Given the folowing class
> >> >>
> >> >> class Ctest{
> >> >> public:
> >> >> Ctest( int i, int j) :a(i) { b = j; }
> >> >> private:
> >> >> int a, b;
> >> >> }
> >> >>
> >> >> When creating an object of type Ctest, what advantage is there to[/color]
> > setting[color=darkred]
> >> >> the member variables a and b using initialization, :a(i), as opposed
> >> >> to using assignment, b = j.
> >> >
> >> > This is answered in the FAQ Lite (you can find it if you follow the
> >> > link http://www.parashift.com/c++-faq-lite/). Please read the FAQ
> >> > before posting.
> >> >
> >> > Victor
> >> Why?[/color]
> > Because[/color]
>
> It seems to me 'Please read the FAQ before posting' could be taken as
> 'Please RTFFAQ'.[/color]

It could just as well be taken at its face value. What's your F point?

Alf P. Steinbach wrote:
[color=blue]
> * "Steven T. Hatton" <susudata@setidava.kushan.aa> schriebt:[color=green]
>>
>> It seems to me 'Please read the FAQ before posting' could be taken as
>> 'Please RTFFAQ'.[/color]
>
> Just spell it out: Read The Fucking Manual.
>
> With prudish & easily offended Americans (who, without noticing any of it,
> offend all others not by their choice of words but by their actions) all
> over the net, however, it is perhaps best not asserted in that form.
>
> It's a mystery to me how MIT could set up the RTFM site in the first
> place, but then MIT has not only the best & brightest of the US
> population, but also
> many bright people from the rest of the world. I am quite sure that in
> current Norway, striving to be more American than the Americans, something
> like the RTFM could never have been set up. But then we no longer have
> any
> technical educational institutions left in Norway -- the miniature MIT
> called NTH was, a few years ago, subsumed by a humanities oriented
> university.
>[/color]

It's not the idea of pointing people to the FAQ that I was addressing. It
was the confrontational undercurrent that seems to lie just below the
surface. Say the wrong thing on the newsgroup and the next thing you know,
you'll have someone going berserk and using profanity in some kind of flame
attacking not only you, but your country, and who knows what else.

Sorry if I don't follow suit by attacking your country. AFAIK, there are
many good people in Norway whom I don't wish to offend.

But the FAQ, does address this issue. Please take a look at the FAQ before
replying. I believe you might find the discussion enlightening.
--
p->m == (*p).m == p[0].m
http://www.kdevelop.org
http://www.suse.com
http://www.mozilla.org

Alf P. Steinbach wrote:
[color=blue]
> * "Steven T. Hatton" <susudata@setidava.kushan.aa> schriebt:[color=green]
>>
>> It seems to me 'Please read the FAQ before posting' could be taken as
>> 'Please RTFFAQ'.[/color]
>
> Just spell it out: Read The Fucking Manual.
>
> With prudish & easily offended Americans (who, without noticing any of it,
> offend all others not by their choice of words but by their actions) all
> over the net, however, it is perhaps best not asserted in that form.
>
> It's a mystery to me how MIT could set up the RTFM site in the first
> place, but then MIT has not only the best & brightest of the US
> population, but also
> many bright people from the rest of the world. I am quite sure that in
> current Norway, striving to be more American than the Americans, something
> like the RTFM could never have been set up. But then we no longer have
> any
> technical educational institutions left in Norway -- the miniature MIT
> called NTH was, a few years ago, subsumed by a humanities oriented
> university.
>[/color]

It's not the idea of pointing people to the FAQ that I was addressing. It
was the confrontational undercurrent that seems to lie just below the
surface. Say the wrong thing on the newsgroup and the next thing you know,
you'll have someone going berserk and using profanity in some kind of flame
attacking not only you, but your country, and who knows what else.

Sorry if I don't follow suit by attacking your country. AFAIK, there are
many good people in Norway whom I don't wish to offend.

But the FAQ, does address this issue. Please take a look at the FAQ before
replying. I believe you might find the discussion enlightening.
--
p->m == (*p).m == p[0].m
http://www.kdevelop.org
http://www.suse.com
http://www.mozilla.org

* "Steven T. Hatton" <susudata@setidava.kushan.aa> schriebt:[color=blue]
> Alf P. Steinbach wrote:
>[color=green]
> > * "Steven T. Hatton" <susudata@setidava.kushan.aa> schriebt:[color=darkred]
> >>
> >> It seems to me 'Please read the FAQ before posting' could be taken as
> >> 'Please RTFFAQ'.[/color]
> >
> > Just spell it out: Read The Fucking Manual.
> >
> > With prudish & easily offended Americans (who, without noticing any of it,
> > offend all others not by their choice of words but by their actions) all
> > over the net, however, it is perhaps best not asserted in that form.
> >
> > It's a mystery to me how MIT could set up the RTFM site in the first
> > place, but then MIT has not only the best & brightest of the US
> > population, but also
> > many bright people from the rest of the world. I am quite sure that in
> > current Norway, striving to be more American than the Americans, something
> > like the RTFM could never have been set up. But then we no longer have
> > any
> > technical educational institutions left in Norway -- the miniature MIT
> > called NTH was, a few years ago, subsumed by a humanities oriented
> > university.
> >[/color]
>
> It's not the idea of pointing people to the FAQ that I was addressing. It
> was the confrontational undercurrent that seems to lie just below the
> surface. Say the wrong thing on the newsgroup and the next thing you know,
> you'll have someone going berserk and using profanity in some kind of flame
> attacking not only you, but your country, and who knows what else.[/color]

Hah, one should never needlessly limit an attack to person and country, as I
am sure your mother told you.

[color=blue]
> Sorry if I don't follow suit by attacking your country. AFAIK, there are
> many good people in Norway whom I don't wish to offend.[/color]

Yada yada yada, "AFAIK there are many good negroes, jews, japs, frogs, etc.,
and one of my best friends is a lesbian". Actually there are. One of the
nice things about Norway is the humanitarian outlook (it's nice in general,
but as commented earlier not so good with respect to technical education).
E.g. we were early (1981) with having a female prime minister (Gro Harlem
Brundtland, <url: http://tinyurl.com/26x63>); then a female and lesbian
minister of justice (Anne Holt, who now mainly writes detective novels, <url:
http://tinyurl.com/34uby>, <url: http://tinyurl.com/yuqcc>), and currently a
male homosexual minister of economy (Per-Kristian Foss, <url:
http://tinyurl.com/3fsdm>) with a priest (Kjell Magne Bondevik, <url:
http://tinyurl.com/2azkv>) as prime minister -- we're simply not bigots, we
don't have that in us, but look at the US... When is the first lesbian
president or even member of Congress expected in the US? Never, I think;
and to take but one little example from current political debate, note that
in Per-Kristian Foss' official CV (from the Norwegian government), referred
above, he lives in a registered partnership -- when is that in the US?

[color=blue]
> But the FAQ, does address this issue. Please take a look at the FAQ before
> replying. I believe you might find the discussion enlightening.[/color]

RTFM on topicality.

--
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail?

Alf P. Steinbach wrote:
[color=blue]
> RTFM on topicality.[/color]
I trust you can find a Norwegian translation of the Hávamál by starting
here: http://www.forn-sed.no/main/nynorsk/informasjon.htm

From the Old Norse:

9. Sá er sæll
er sjálfr of á
lof ok vit, meðan lifir;
því at ill ráð
hefr maðr oft þegit
annars brjóstum ór.

10. Byrði betri
berr-at maðr brautu at
en sé mannvit mikit;
auði betra
þykkir þat í ókunnum stað;
slíkt er válaðs vera.

11. Byrði betri
berr-at maðr brautu at
en sé mannvit mikit;
vegnest verra
vegr-a hann velli at
en sé ofdrykkja öls.

12. Er-a svá gótt
sem gótt kveða
öl alda sonum,
því at færa veit
er fleira drekkr
síns til geðs gumi.

13. Óminnishegri heitir
sá er yfir ölðrum þrumir;
hann stelr geði guma;
þess fugls fjöðrum
ek fjötraðr vark
í garði Gunnlaðar.
--
p->m == (*p).m == p[0].m
http://www.kdevelop.org
http://www.suse.com
http://www.mozilla.org

* "Steven T. Hatton" <susudata@setidava.kushan.aa> schriebt:[color=blue]
> Alf P. Steinbach wrote:
>[color=green]
> > * "Steven T. Hatton" <susudata@setidava.kushan.aa> schriebt:[color=darkred]
> >>
> >> It seems to me 'Please read the FAQ before posting' could be taken as
> >> 'Please RTFFAQ'.[/color]
> >
> > Just spell it out: Read The Fucking Manual.
> >
> > With prudish & easily offended Americans (who, without noticing any of it,
> > offend all others not by their choice of words but by their actions) all
> > over the net, however, it is perhaps best not asserted in that form.
> >
> > It's a mystery to me how MIT could set up the RTFM site in the first
> > place, but then MIT has not only the best & brightest of the US
> > population, but also
> > many bright people from the rest of the world. I am quite sure that in
> > current Norway, striving to be more American than the Americans, something
> > like the RTFM could never have been set up. But then we no longer have
> > any
> > technical educational institutions left in Norway -- the miniature MIT
> > called NTH was, a few years ago, subsumed by a humanities oriented
> > university.
> >[/color]
>
> It's not the idea of pointing people to the FAQ that I was addressing. It
> was the confrontational undercurrent that seems to lie just below the
> surface. Say the wrong thing on the newsgroup and the next thing you know,
> you'll have someone going berserk and using profanity in some kind of flame
> attacking not only you, but your country, and who knows what else.[/color]

Hah, one should never needlessly limit an attack to person and country, as I
am sure your mother told you.

[color=blue]
> Sorry if I don't follow suit by attacking your country. AFAIK, there are
> many good people in Norway whom I don't wish to offend.[/color]

Yada yada yada, "AFAIK there are many good negroes, jews, japs, frogs, etc.,
and one of my best friends is a lesbian". Actually there are. One of the
nice things about Norway is the humanitarian outlook (it's nice in general,
but as commented earlier not so good with respect to technical education).
E.g. we were early (1981) with having a female prime minister (Gro Harlem
Brundtland, <url: http://tinyurl.com/26x63>); then a female and lesbian
minister of justice (Anne Holt, who now mainly writes detective novels, <url:
http://tinyurl.com/34uby>, <url: http://tinyurl.com/yuqcc>), and currently a
male homosexual minister of economy (Per-Kristian Foss, <url:
http://tinyurl.com/3fsdm>) with a priest (Kjell Magne Bondevik, <url:
http://tinyurl.com/2azkv>) as prime minister -- we're simply not bigots, we
don't have that in us, but look at the US... When is the first lesbian
president or even member of Congress expected in the US? Never, I think;
and to take but one little example from current political debate, note that
in Per-Kristian Foss' official CV (from the Norwegian government), referred
above, he lives in a registered partnership -- when is that in the US?

[color=blue]
> But the FAQ, does address this issue. Please take a look at the FAQ before
> replying. I believe you might find the discussion enlightening.[/color]

RTFM on topicality.

--
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail?

Alf P. Steinbach wrote:
[color=blue]
> RTFM on topicality.[/color]
I trust you can find a Norwegian translation of the Hávamál by starting
here: http://www.forn-sed.no/main/nynorsk/informasjon.htm

From the Old Norse:

9. Sá er sæll
er sjálfr of á
lof ok vit, meðan lifir;
því at ill ráð
hefr maðr oft þegit
annars brjóstum ór.

10. Byrði betri
berr-at maðr brautu at
en sé mannvit mikit;
auði betra
þykkir þat í ókunnum stað;
slíkt er válaðs vera.

11. Byrði betri
berr-at maðr brautu at
en sé mannvit mikit;
vegnest verra
vegr-a hann velli at
en sé ofdrykkja öls.

12. Er-a svá gótt
sem gótt kveða
öl alda sonum,
því at færa veit
er fleira drekkr
síns til geðs gumi.

13. Óminnishegri heitir
sá er yfir ölðrum þrumir;
hann stelr geði guma;
þess fugls fjöðrum
ek fjötraðr vark
í garði Gunnlaðar.
--
p->m == (*p).m == p[0].m
http://www.kdevelop.org
http://www.suse.com
http://www.mozilla.org

* "Steven T. Hatton" <susudata@setidava.kushan.aa> schriebt:[color=blue]
>
> I trust you can find a Norwegian translation of the Hávamál[/color]

The English translation is actually more understandable.

Have you considered verses 1 through 8, not just 9 through 13? ;-)

Seriously, please don't more times suggest that the ordinary and polite
way to steer someone to the FAQ -- as Victor did -- is equivalent to
RTFFAQ. What you did there was to break two rules for visitors to the
house. Hinting (it seemed like) about Victor's motives, like "so you
really meant [bad thing]", and second, like "your customs are ungood".

Now I've tried both humor, low-intensity flaming and simple explanation.

I should perhaps have tried the last first, but done is done.

Cheers,

- Alf

--
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail?

PS: My information about the US Congress turned out to be out of date.
It actually had Tammy Baldwin in 1998. So my guess was partially
incorrect.

--
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail?

* "Steven T. Hatton" <susudata@setidava.kushan.aa> schriebt:[color=blue]
>
> I trust you can find a Norwegian translation of the Hávamál[/color]

The English translation is actually more understandable.

Have you considered verses 1 through 8, not just 9 through 13? ;-)

Seriously, please don't more times suggest that the ordinary and polite
way to steer someone to the FAQ -- as Victor did -- is equivalent to
RTFFAQ. What you did there was to break two rules for visitors to the
house. Hinting (it seemed like) about Victor's motives, like "so you
really meant [bad thing]", and second, like "your customs are ungood".

Now I've tried both humor, low-intensity flaming and simple explanation.

I should perhaps have tried the last first, but done is done.

Cheers,

- Alf

--
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail?

PS: My information about the US Congress turned out to be out of date.
It actually had Tammy Baldwin in 1998. So my guess was partially
incorrect.

--
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail?

Alf P. Steinbach wrote:
[color=blue]
> * "Steven T. Hatton" <susudata@setidava.kushan.aa> schriebt:[color=green]
>>
>> I trust you can find a Norwegian translation of the Hávamál[/color]
>
> The English translation is actually more understandable.[/color]

They all seem lacking to me. I prefer the Old Norse.
[color=blue]
> Have you considered verses 1 through 8, not just 9 through 13? ;-)[/color]

Certainly, but they didn't seem as apropos.
[color=blue]
> Seriously, please don't more times suggest that the ordinary and polite
> way to steer someone to the FAQ -- as Victor did -- is equivalent to
> RTFFAQ.[/color]

I didn't say it was equivalent. I said it might be taken that way.
[color=blue]
> What you did there was to break two rules for visitors to the
> house. Hinting (it seemed like) about Victor's motives, like "so you
> really meant [bad thing]", and second, like "your customs are ungood".[/color]

I still don't fully understand /why/ m_x(x) works in the following:

#include <iostream>

class A {
int m_x;
public:
A(int x):m_x(x){};
int getX(){return m_x; };
};

int main(int argc, char* argv[]) {
A a(5);
std::cout << a.getX() << std::endl;
}
[color=blue]
> Now I've tried both humor, low-intensity flaming and simple explanation.
>
> I should perhaps have tried the last first, but done is done.
>
>
> Cheers,
>
> - Alf[/color]

What Gore really meant when he pointed to his work with the Internet was not
that he invented the Internet - which he never said - but that he did a lot
to popularize it, and disseminate information about the use of web browsers
to people in prominant and influential positions. I set up the systems he
use to do it.

--
p->m == (*p).m == p[0].m
http://www.kdevelop.org
http://www.suse.com
http://www.mozilla.org

* "Steven T. Hatton" <susudata@setidava.kushan.aa> schriebt:[color=blue]
>
> I still don't fully understand /why/ m_x(x) works in the following:
>
> #include <iostream>
>
> class A {
> int m_x;
> public:
> A(int x):m_x(x){};
> int getX(){return m_x; };
> };
>
> int main(int argc, char* argv[]) {
> A a(5);
> std::cout << a.getX() << std::endl;
> }[/color]

I guess you mean why it should be preferred over assignment. In this
case, with 'int' type, and nothing else going on in the constructor, I
see no technical reason and no readability reason. But it's like
a car driver indicating which way he's about to drive at crossroads even
when there are no other cars in sight: the habit helps to do the Right
Thing in general, and perhaps there's someone waiting to cross the
street, just not very clearly in sight, making the decision to cross...

Btw., by declaring 'getX' as a 'const' member function it will be
possible to call it also on 'const' A-objects.

[color=blue]
> What Gore really meant when he pointed to his work with the Internet was not
> that he invented the Internet - which he never said - but that he did a lot
> to popularize it, and disseminate information about the use of web browsers
> to people in prominant and influential positions. I set up the systems he
> use to do it.[/color]

I'm not sure whether this is some subtle thing or a hint about off-topicality
or an effort to convince me that you are no dummy (I do know, at least if
earlier comments about implementing mathematical models is true), or boasting,
or what. But it doesn't seem very relevant. If it's simply "by the way I met
a famous person", well most of us have; e.g. I shook hands with Bill Clinton
last time he was in Oslo -- I was prevented from leaving the entrance to a
shop by security guards, then came Bill, and of course he had to shake hands
with a beautiful lady beside me, and another one, and then for consistency
with me too as the last person before the entrance to the shop. Later the
same week I met a famous (in Norway and Italy) Norwegian pop-star, Lene
Marlin, or at least I think I did, but being afraid that possibly it wasn't
her I didn't dare to say hello. Barring a major fault in the pop-star
recognition circuits, however, I think I met two very famous persons in the
span of just one week, and actually shook hands with one of them!

--
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail?

Alf P. Steinbach wrote:
[color=blue]
> * "Steven T. Hatton" <susudata@setidava.kushan.aa> schriebt:[color=green]
>>
>> I trust you can find a Norwegian translation of the Hávamál[/color]
>
> The English translation is actually more understandable.[/color]

They all seem lacking to me. I prefer the Old Norse.
[color=blue]
> Have you considered verses 1 through 8, not just 9 through 13? ;-)[/color]

Certainly, but they didn't seem as apropos.
[color=blue]
> Seriously, please don't more times suggest that the ordinary and polite
> way to steer someone to the FAQ -- as Victor did -- is equivalent to
> RTFFAQ.[/color]

I didn't say it was equivalent. I said it might be taken that way.
[color=blue]
> What you did there was to break two rules for visitors to the
> house. Hinting (it seemed like) about Victor's motives, like "so you
> really meant [bad thing]", and second, like "your customs are ungood".[/color]

I still don't fully understand /why/ m_x(x) works in the following:

#include <iostream>

class A {
int m_x;
public:
A(int x):m_x(x){};
int getX(){return m_x; };
};

int main(int argc, char* argv[]) {
A a(5);
std::cout << a.getX() << std::endl;
}
[color=blue]
> Now I've tried both humor, low-intensity flaming and simple explanation.
>
> I should perhaps have tried the last first, but done is done.
>
>
> Cheers,
>
> - Alf[/color]

What Gore really meant when he pointed to his work with the Internet was not
that he invented the Internet - which he never said - but that he did a lot
to popularize it, and disseminate information about the use of web browsers
to people in prominant and influential positions. I set up the systems he
use to do it.

--
p->m == (*p).m == p[0].m
http://www.kdevelop.org
http://www.suse.com
http://www.mozilla.org

Alf P. Steinbach wrote:
[color=blue]
> * "Steven T. Hatton" <susudata@setidava.kushan.aa> schriebt:[color=green]
>>
>> I still don't fully understand /why/ m_x(x) works in the following:
>>
>> #include <iostream>
>>
>> class A {
>> int m_x;
>> public:
>> A(int x):m_x(x){};[/color][/color]
[color=blue]
> I guess you mean why it should be preferred over assignment.[/color]

I don't know what formal language principle underlies the mechanism. That's
why I'm sitting here with the Standard and a highlighter. Yes, it's in
hardcopy printed using psutils. I'm not using the highlighter on the
electronic version in PDF! :-)
[color=blue]
> Btw., by declaring 'getX' as a 'const' member function it will be
> possible to call it also on 'const' A-objects.[/color]

Thanks for the pointer, I still have a lot to internalize.[color=blue]
>[color=green]
>> What Gore really meant when he pointed to his work with the Internet was
>> not that he invented the Internet - which he never said - but that he did
>> a lot to popularize it, and disseminate information about the use of web
>> browsers
>> to people in prominant and influential positions. I set up the systems
>> he use to do it.[/color]
>
> I'm not sure whether this is some subtle thing[/color]

The point was I might be a bit new to this particular newsgroup, but I'm not
new to usenet. At some point I'm no longer a newbie in this newsgroup.
For me to comment on how others are treated is not necessarily improper for
a guest (the Hávamál is the song of a wandering singer), but I think I've
been around long enough to not qualify as a newbie.
[color=blue]
> But it doesn't seem very relevant. If it's simply "by the way I[/color]
[color=blue]
> met a famous person", well most of us have; e.g. I shook hands with Bill
> Clinton
> last time he was in Oslo -- I was prevented from leaving the entrance to[color=green]
> > a shop by security guards, then came Bill,[/color]
> and then for consistency with me too as the last person before the[color=green]
> > entrance to the shop.[/color][/color]

I hope you washed your hand with hot water and soap before touching
anything, especially your face, or other sensitive part of your body.
[color=blue]
> Later the
> same week I met a famous (in Norway and Italy) Norwegian pop-star, Lene
> Marlin, or at least I think I did, but being afraid that possibly it
> wasn't
> her I didn't dare to say hello. Barring a major fault in the pop-star
> recognition circuits, however, I think I met two very famous persons in
> the span of just one week, and actually shook hands with one of them![/color]

I met Stephen Wolfram, and didn't even know it at the time. I never met
Gore, I just set up the systems. I'm far more pleased to have had a chance
to meet and interact with John A. Wheeler, than I would be to have met
Gore.

http://pupgg.princeton.edu/www/jh/an...symposium.html

--
p->m == (*p).m == p[0].m
http://www.kdevelop.org
http://www.suse.com
http://www.mozilla.org

* "Steven T. Hatton" <susudata@setidava.kushan.aa> schriebt:[color=blue]
>
> I still don't fully understand /why/ m_x(x) works in the following:
>
> #include <iostream>
>
> class A {
> int m_x;
> public:
> A(int x):m_x(x){};
> int getX(){return m_x; };
> };
>
> int main(int argc, char* argv[]) {
> A a(5);
> std::cout << a.getX() << std::endl;
> }[/color]

I guess you mean why it should be preferred over assignment. In this
case, with 'int' type, and nothing else going on in the constructor, I
see no technical reason and no readability reason. But it's like
a car driver indicating which way he's about to drive at crossroads even
when there are no other cars in sight: the habit helps to do the Right
Thing in general, and perhaps there's someone waiting to cross the
street, just not very clearly in sight, making the decision to cross...

Btw., by declaring 'getX' as a 'const' member function it will be
possible to call it also on 'const' A-objects.

[color=blue]
> What Gore really meant when he pointed to his work with the Internet was not
> that he invented the Internet - which he never said - but that he did a lot
> to popularize it, and disseminate information about the use of web browsers
> to people in prominant and influential positions. I set up the systems he
> use to do it.[/color]

I'm not sure whether this is some subtle thing or a hint about off-topicality
or an effort to convince me that you are no dummy (I do know, at least if
earlier comments about implementing mathematical models is true), or boasting,
or what. But it doesn't seem very relevant. If it's simply "by the way I met
a famous person", well most of us have; e.g. I shook hands with Bill Clinton
last time he was in Oslo -- I was prevented from leaving the entrance to a
shop by security guards, then came Bill, and of course he had to shake hands
with a beautiful lady beside me, and another one, and then for consistency
with me too as the last person before the entrance to the shop. Later the
same week I met a famous (in Norway and Italy) Norwegian pop-star, Lene
Marlin, or at least I think I did, but being afraid that possibly it wasn't
her I didn't dare to say hello. Barring a major fault in the pop-star
recognition circuits, however, I think I met two very famous persons in the
span of just one week, and actually shook hands with one of them!

--
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail?

Alf P. Steinbach wrote:
[color=blue]
> * "Steven T. Hatton" <susudata@setidava.kushan.aa> schriebt:[color=green]
>>
>> I still don't fully understand /why/ m_x(x) works in the following:
>>
>> #include <iostream>
>>
>> class A {
>> int m_x;
>> public:
>> A(int x):m_x(x){};[/color][/color]
[color=blue]
> I guess you mean why it should be preferred over assignment.[/color]

I don't know what formal language principle underlies the mechanism. That's
why I'm sitting here with the Standard and a highlighter. Yes, it's in
hardcopy printed using psutils. I'm not using the highlighter on the
electronic version in PDF! :-)
[color=blue]
> Btw., by declaring 'getX' as a 'const' member function it will be
> possible to call it also on 'const' A-objects.[/color]

Thanks for the pointer, I still have a lot to internalize.[color=blue]
>[color=green]
>> What Gore really meant when he pointed to his work with the Internet was
>> not that he invented the Internet - which he never said - but that he did
>> a lot to popularize it, and disseminate information about the use of web
>> browsers
>> to people in prominant and influential positions. I set up the systems
>> he use to do it.[/color]
>
> I'm not sure whether this is some subtle thing[/color]

The point was I might be a bit new to this particular newsgroup, but I'm not
new to usenet. At some point I'm no longer a newbie in this newsgroup.
For me to comment on how others are treated is not necessarily improper for
a guest (the Hávamál is the song of a wandering singer), but I think I've
been around long enough to not qualify as a newbie.
[color=blue]
> But it doesn't seem very relevant. If it's simply "by the way I[/color]
[color=blue]
> met a famous person", well most of us have; e.g. I shook hands with Bill
> Clinton
> last time he was in Oslo -- I was prevented from leaving the entrance to[color=green]
> > a shop by security guards, then came Bill,[/color]
> and then for consistency with me too as the last person before the[color=green]
> > entrance to the shop.[/color][/color]

I hope you washed your hand with hot water and soap before touching
anything, especially your face, or other sensitive part of your body.
[color=blue]
> Later the
> same week I met a famous (in Norway and Italy) Norwegian pop-star, Lene
> Marlin, or at least I think I did, but being afraid that possibly it
> wasn't
> her I didn't dare to say hello. Barring a major fault in the pop-star
> recognition circuits, however, I think I met two very famous persons in
> the span of just one week, and actually shook hands with one of them![/color]

I met Stephen Wolfram, and didn't even know it at the time. I never met
Gore, I just set up the systems. I'm far more pleased to have had a chance
to meet and interact with John A. Wheeler, than I would be to have met
Gore.

http://pupgg.princeton.edu/www/jh/an...symposium.html

--
p->m == (*p).m == p[0].m
http://www.kdevelop.org
http://www.suse.com
http://www.mozilla.org

* "Steven T. Hatton" <susudata@setidava.kushan.aa> schriebt:[color=blue]
> Alf P. Steinbach wrote:
>[color=green]
> > * "Steven T. Hatton" <susudata@setidava.kushan.aa> schriebt:[color=darkred]
> >>
> >> I still don't fully understand /why/ m_x(x) works in the following:
> >>
> >> #include <iostream>
> >>
> >> class A {
> >> int m_x;
> >> public:
> >> A(int x):m_x(x){};[/color][/color]
>[color=green]
> > I guess you mean why it should be preferred over assignment.[/color]
>
> I don't know what formal language principle underlies the mechanism. That's
> why I'm sitting here with the Standard and a highlighter. Yes, it's in
> hardcopy printed using psutils. I'm not using the highlighter on the
> electronic version in PDF! :-)[/color]

Again I'm not quite sure what you mean. But possibility 1: what you mean by
formal language mechanism is the C++ definition of initializer list. You'll
find that in section §12.6.2 of the Holy Standard. With the colon it's
called a ctor-initializer, and sans the colon it's a mem-initializer-list.

Possibility 2: what you mean by formal language mechanism is a language-
independent thing that §12.6.2 is the C++ language implementation of. Sorry,
can't help you there. Except that it's possible to find formal definitions
of just about anything just by looking and searching hard enough; and if one
does not exist it can always be produced.

Possibility 3: what you mean by formal language mechanism is what purpose
does it serve, when e.g. Java seems to do well without it? Well, one thing
that is different between Java and C++ is that a Java object of a type with
constructor can only be referred to by reference, whereas in C++ it can be
a local variable say (or directly occupy storage in another object, or
static storage). To ensure type safety -- that all member objects with
constructors have their constructors called -- the language design choice
is then between (A) not having automatic constructor calls but instead require
the equivalent of placement new for all subobjects, one can't just leave the
members as null-references as in Java, and (B) having automatic constructor
calls, in which case additional initialization in the constructor body will
be inefficient, and there is the problem of providing constructor arguments.
C++ uses solution (B), and solves the both inefficiency problem and the
argument passing problem with the constructor initializer lists mechanism.

In addition constructor initializer lists solve the problem of initializing
const members.

But an alternative to that could be not to design the language with const
members but with 'readonly' members which turn to 'readonly' state only
after the constructor has finished.

[color=blue]
> I met Stephen Wolfram, and didn't even know it at the time.[/color]

You would have been infected with cellular automata. But I rather liked
his program for displaying Sierpinski-like triangles. Since this is a C++
newsgroup, here's the Perl version, courtesy of Lars Christian Jensen:

perl -e 'for$a(0..63){for(0..$a){print($_&~$a?" ":"#")}print"\n"}'

[color=blue]
> John A. Wheeler[/color]

For some reason he reminds me of the book "wheelers" by Ian Stewart... ;-)

--
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail?

Alf P. Steinbach wrote:
[color=blue]
> * "Steven T. Hatton" <susudata@setidava.kushan.aa> schriebt:[color=green]
>> Alf P. Steinbach wrote:
>>[color=darkred]
>> > * "Steven T. Hatton" <susudata@setidava.kushan.aa> schriebt:
>> >>
>> >> I still don't fully understand /why/ m_x(x) works in the following:
>> >>
>> >> #include <iostream>
>> >>
>> >> class A {
>> >> int m_x;
>> >> public:
>> >> A(int x):m_x(x){};[/color]
>>[color=darkred]
>> > I guess you mean why it should be preferred over assignment.[/color]
>>
>> I don't know what formal language principle underlies the mechanism.
>> That's why I'm sitting here with the Standard and a highlighter. Yes,
>> it's in hardcopy printed using psutils. I'm not using the highlighter on
>> the electronic version in PDF! :-)[/color]
>
> Again I'm not quite sure what you mean. But possibility 1: what you mean
> by
> formal language mechanism is the C++ definition of initializer list.
> You'll
> find that in section §12.6.2 of the Holy Standard. With the colon it's
> called a ctor-initializer, and sans the colon it's a mem-initializer-list.[/color]

Thanks for the pointer. But that's not what has me puzzled.
[color=blue]
> Possibility 2: what you mean by formal language mechanism is a language-
> independent thing that §12.6.2 is the C++ language implementation of.[/color]

I don't believe it's an implementation issue.
[color=blue]
> Sorry,
> can't help you there. Except that it's possible to find formal
> definitions of just about anything just by looking and searching hard
> enough; and if one does not exist it can always be produced.[/color]

Nobody ever responded to my question about what else significant is on the
page of K&R in the Grammar where the function main() is specified. I
wonder why.
[color=blue]
> Possibility 3: what you mean by formal language mechanism is what purpose
> does it serve, when e.g. Java seems to do well without it?[/color]

Nope.
[color=blue]
> Well, one
> thing that is different between Java and C++ is that a Java object of a
> type with constructor can only be referred to by reference, whereas in C++
> it can be a local variable say (or directly occupy storage in another
> object, or
> static storage). To ensure type safety -- that all member objects with
> constructors have their constructors called -- the language design
> choice is then between (A) not having automatic constructor calls but
> instead require the equivalent of placement new for all subobjects, one
> can't just leave the members as null-references as in Java, and (B) having
> automatic constructor calls, in which case additional initialization in
> the constructor body will be inefficient, and there is the problem of
> providing constructor arguments. C++ uses solution (B), and solves the
> both inefficiency problem and the argument passing problem with the
> constructor initializer lists mechanism.[/color]

I guess there are advantages to any of the approaches. Java is a very
regular language which may be a bit awkward at times, but it's also
straightforward. C++ reminds me of something Mithrandir might study. There
seems to be a lot of magic in it. Hard to master, hard to perceive, but
powerful when you do master it.

Here's the question. Where (how) does the Holy Standard specify that I can
do this:

int main(int argc, char* argv[]) {
int i(3); // <---<---
std::cout <<"i = " <> I met Stephen Wolfram, and didn't even know it at the time.[/color]
>
> You would have been infected with cellular automata. But I rather liked
> his program for displaying Sierpinski-like triangles. Since this is a C++
> newsgroup, here's the Perl version, courtesy of Lars Christian Jensen:[/color]

I don't know if I'm susceptible to fullblown Cellular Automata. I've done a
lot of fun stuff in Mathematica, but there is something fundamental I have
yet to grasp. It may be something it shares with Lisp, which I've never
mastered. I know it has to do with up-values. But I don't even want to
think about that right now.
[color=blue]
> perl -e 'for$a(0..63){for(0..$a){print($_&~$a?" ":"#")}print"\n"}'[/color]

And you suggested "UBC" was profane in C++ circles? ;-)
[color=blue]
>[color=green]
>> John A. Wheeler[/color]
>
> For some reason he reminds me of the book "wheelers" by Ian Stewart... ;-)[/color]

Don't know the book, but this will tell you more about Wheeler:
http://www.usd.edu/phys/courses/phys...k/wheeler.html
--
p->m == (*p).m == p[0].m
http://www.kdevelop.org
http://www.suse.com
http://www.mozilla.org

* "Steven T. Hatton" <susudata@setidava.kushan.aa> schriebt:[color=blue]
> Alf P. Steinbach wrote:
>[color=green]
> > * "Steven T. Hatton" <susudata@setidava.kushan.aa> schriebt:[color=darkred]
> >>
> >> I still don't fully understand /why/ m_x(x) works in the following:
> >>
> >> #include <iostream>
> >>
> >> class A {
> >> int m_x;
> >> public:
> >> A(int x):m_x(x){};[/color][/color]
>[color=green]
> > I guess you mean why it should be preferred over assignment.[/color]
>
> I don't know what formal language principle underlies the mechanism. That's
> why I'm sitting here with the Standard and a highlighter. Yes, it's in
> hardcopy printed using psutils. I'm not using the highlighter on the
> electronic version in PDF! :-)[/color]

Again I'm not quite sure what you mean. But possibility 1: what you mean by
formal language mechanism is the C++ definition of initializer list. You'll
find that in section §12.6.2 of the Holy Standard. With the colon it's
called a ctor-initializer, and sans the colon it's a mem-initializer-list.

Possibility 2: what you mean by formal language mechanism is a language-
independent thing that §12.6.2 is the C++ language implementation of. Sorry,
can't help you there. Except that it's possible to find formal definitions
of just about anything just by looking and searching hard enough; and if one
does not exist it can always be produced.

Possibility 3: what you mean by formal language mechanism is what purpose
does it serve, when e.g. Java seems to do well without it? Well, one thing
that is different between Java and C++ is that a Java object of a type with
constructor can only be referred to by reference, whereas in C++ it can be
a local variable say (or directly occupy storage in another object, or
static storage). To ensure type safety -- that all member objects with
constructors have their constructors called -- the language design choice
is then between (A) not having automatic constructor calls but instead require
the equivalent of placement new for all subobjects, one can't just leave the
members as null-references as in Java, and (B) having automatic constructor
calls, in which case additional initialization in the constructor body will
be inefficient, and there is the problem of providing constructor arguments.
C++ uses solution (B), and solves the both inefficiency problem and the
argument passing problem with the constructor initializer lists mechanism.

In addition constructor initializer lists solve the problem of initializing
const members.

But an alternative to that could be not to design the language with const
members but with 'readonly' members which turn to 'readonly' state only
after the constructor has finished.

[color=blue]
> I met Stephen Wolfram, and didn't even know it at the time.[/color]

You would have been infected with cellular automata. But I rather liked
his program for displaying Sierpinski-like triangles. Since this is a C++
newsgroup, here's the Perl version, courtesy of Lars Christian Jensen:

perl -e 'for$a(0..63){for(0..$a){print($_&~$a?" ":"#")}print"\n"}'

[color=blue]
> John A. Wheeler[/color]

For some reason he reminds me of the book "wheelers" by Ian Stewart... ;-)

--
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail?

* "Steven T. Hatton" <susudata@setidava.kushan.aa> schriebt:[color=blue]
> Here's the question. Where (how) does the Holy Standard specify that I can
> do this:
>
> int main(int argc, char* argv[]) {
> int i(3); // <---<---
> std::cout <<"i = " < }[/color]

Well that's another thing entirely. That's a "pseudo constructor
call". There's also "pseudo destructor call", but leave that for
the moment.

The standard (I'll leave off the mysticism for now, guess you had
enough of that in your meeting with Wheeler) discusses this in (click
on cpp.pdf, type ctrl-f, type in "pseudo constructor", nope, remember
that it is really cast notation, check §5.4, referred to §5.2.3 by
§5.4/2) §5.2.3/1 "Explicit type conversion (functional notation)".

This isn't homework, I hope?

--
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail?

Alf P. Steinbach wrote:
[color=blue]
> * "Steven T. Hatton" <susudata@setidava.kushan.aa> schriebt:[color=green]
>> Alf P. Steinbach wrote:
>>[color=darkred]
>> > * "Steven T. Hatton" <susudata@setidava.kushan.aa> schriebt:
>> >>
>> >> I still don't fully understand /why/ m_x(x) works in the following:
>> >>
>> >> #include <iostream>
>> >>
>> >> class A {
>> >> int m_x;
>> >> public:
>> >> A(int x):m_x(x){};[/color]
>>[color=darkred]
>> > I guess you mean why it should be preferred over assignment.[/color]
>>
>> I don't know what formal language principle underlies the mechanism.
>> That's why I'm sitting here with the Standard and a highlighter. Yes,
>> it's in hardcopy printed using psutils. I'm not using the highlighter on
>> the electronic version in PDF! :-)[/color]
>
> Again I'm not quite sure what you mean. But possibility 1: what you mean
> by
> formal language mechanism is the C++ definition of initializer list.
> You'll
> find that in section §12.6.2 of the Holy Standard. With the colon it's
> called a ctor-initializer, and sans the colon it's a mem-initializer-list.[/color]

Thanks for the pointer. But that's not what has me puzzled.
[color=blue]
> Possibility 2: what you mean by formal language mechanism is a language-
> independent thing that §12.6.2 is the C++ language implementation of.[/color]

I don't believe it's an implementation issue.
[color=blue]
> Sorry,
> can't help you there. Except that it's possible to find formal
> definitions of just about anything just by looking and searching hard
> enough; and if one does not exist it can always be produced.[/color]

Nobody ever responded to my question about what else significant is on the
page of K&R in the Grammar where the function main() is specified. I
wonder why.
[color=blue]
> Possibility 3: what you mean by formal language mechanism is what purpose
> does it serve, when e.g. Java seems to do well without it?[/color]

Nope.
[color=blue]
> Well, one
> thing that is different between Java and C++ is that a Java object of a
> type with constructor can only be referred to by reference, whereas in C++
> it can be a local variable say (or directly occupy storage in another
> object, or
> static storage). To ensure type safety -- that all member objects with
> constructors have their constructors called -- the language design
> choice is then between (A) not having automatic constructor calls but
> instead require the equivalent of placement new for all subobjects, one
> can't just leave the members as null-references as in Java, and (B) having
> automatic constructor calls, in which case additional initialization in
> the constructor body will be inefficient, and there is the problem of
> providing constructor arguments. C++ uses solution (B), and solves the
> both inefficiency problem and the argument passing problem with the
> constructor initializer lists mechanism.[/color]

I guess there are advantages to any of the approaches. Java is a very
regular language which may be a bit awkward at times, but it's also
straightforward. C++ reminds me of something Mithrandir might study. There
seems to be a lot of magic in it. Hard to master, hard to perceive, but
powerful when you do master it.

Here's the question. Where (how) does the Holy Standard specify that I can
do this:

int main(int argc, char* argv[]) {
int i(3); // <---<---
std::cout <<"i = " <> I met Stephen Wolfram, and didn't even know it at the time.[/color]
>
> You would have been infected with cellular automata. But I rather liked
> his program for displaying Sierpinski-like triangles. Since this is a C++
> newsgroup, here's the Perl version, courtesy of Lars Christian Jensen:[/color]

I don't know if I'm susceptible to fullblown Cellular Automata. I've done a
lot of fun stuff in Mathematica, but there is something fundamental I have
yet to grasp. It may be something it shares with Lisp, which I've never
mastered. I know it has to do with up-values. But I don't even want to
think about that right now.
[color=blue]
> perl -e 'for$a(0..63){for(0..$a){print($_&~$a?" ":"#")}print"\n"}'[/color]

And you suggested "UBC" was profane in C++ circles? ;-)
[color=blue]
>[color=green]
>> John A. Wheeler[/color]
>
> For some reason he reminds me of the book "wheelers" by Ian Stewart... ;-)[/color]

Don't know the book, but this will tell you more about Wheeler:
http://www.usd.edu/phys/courses/phys...k/wheeler.html
--
p->m == (*p).m == p[0].m
http://www.kdevelop.org
http://www.suse.com
http://www.mozilla.org

* "Steven T. Hatton" <susudata@setidava.kushan.aa> schriebt:[color=blue]
> Here's the question. Where (how) does the Holy Standard specify that I can
> do this:
>
> int main(int argc, char* argv[]) {
> int i(3); // <---<---
> std::cout <<"i = " < }[/color]

Well that's another thing entirely. That's a "pseudo constructor
call". There's also "pseudo destructor call", but leave that for
the moment.

The standard (I'll leave off the mysticism for now, guess you had
enough of that in your meeting with Wheeler) discusses this in (click
on cpp.pdf, type ctrl-f, type in "pseudo constructor", nope, remember
that it is really cast notation, check §5.4, referred to §5.2.3 by
§5.4/2) §5.2.3/1 "Explicit type conversion (functional notation)".

This isn't homework, I hope?

--
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail?

Alf P. Steinbach wrote:
[color=blue]
> * "Steven T. Hatton" <susudata@setidava.kushan.aa> schriebt:[color=green]
>> Here's the question. Where (how) does the Holy Standard specify that I
>> can do this:
>>
>> int main(int argc, char* argv[]) {
>> int i(3); // <---<---
>> std::cout <<"i = " <> }[/color]
>
> Well that's another thing entirely. That's a "pseudo constructor
> call". There's also "pseudo destructor call", but leave that for
> the moment.
>
> The standard (I'll leave off the mysticism for now, guess you had
> enough of that in your meeting with Wheeler) discusses this in (click
> on cpp.pdf, type ctrl-f, type in "pseudo constructor", nope, remember
> that it is really cast notation, check §5.4, referred to §5.2.3 by
> §5.4/2) §5.2.3/1 "Explicit type conversion (functional notation)".[/color]

Thanks!
[color=blue]
> This isn't homework, I hope?
>[/color]
No, it's the first question I asked in this newsgroup. Your response was
along the lines 'one might presume you would find that in the book'. But
you thought I was asking one of the questins you listed previously in this
thread. ;-)
--
p->m == (*p).m == p[0].m
http://www.kdevelop.org
http://www.suse.com
http://www.mozilla.org

"Steven T. Hatton" <susudata@setidava.kushan.aa> wrote[color=blue]
>
> [more snipping than you can shake a stick at]
>
> Here's the question. Where (how) does the Holy Standard
> specify that I can do this:
>
> int main(int argc, char* argv[]) {
> int i(3); // <---<---
> std::cout <<"i = " < }[/color]

8.5 (Initializers):

initializer:
= initializer clause
( expression-list )

.... and so on.

Claudio Puviani

Alf P. Steinbach wrote:
[color=blue]
> * "Steven T. Hatton" <susudata@setidava.kushan.aa> schriebt:[color=green]
>> Here's the question. Where (how) does the Holy Standard specify that I
>> can do this:
>>
>> int main(int argc, char* argv[]) {
>> int i(3); // <---<---
>> std::cout <<"i = " <> }[/color]
>
> Well that's another thing entirely. That's a "pseudo constructor
> call". There's also "pseudo destructor call", but leave that for
> the moment.
>
> The standard (I'll leave off the mysticism for now, guess you had
> enough of that in your meeting with Wheeler) discusses this in (click
> on cpp.pdf, type ctrl-f, type in "pseudo constructor", nope, remember
> that it is really cast notation, check §5.4, referred to §5.2.3 by
> §5.4/2) §5.2.3/1 "Explicit type conversion (functional notation)".[/color]

Thanks!
[color=blue]
> This isn't homework, I hope?
>[/color]
No, it's the first question I asked in this newsgroup. Your response was
along the lines 'one might presume you would find that in the book'. But
you thought I was asking one of the questins you listed previously in this
thread. ;-)
--
p->m == (*p).m == p[0].m
http://www.kdevelop.org
http://www.suse.com
http://www.mozilla.org

* alfps@start.no (Alf P. Steinbach) schriebt:[color=blue]
> * "Steven T. Hatton" <susudata@setidava.kushan.aa> schriebt:[color=green]
> > Here's the question. Where (how) does the Holy Standard specify that I can
> > do this:
> >
> > int main(int argc, char* argv[]) {
> > int i(3); // <---<---
> > std::cout <<"i = " < > }[/color]
>
> Well that's another thing entirely. That's a "pseudo constructor
> call". There's also "pseudo destructor call", but leave that for
> the moment.
>
> The standard (I'll leave off the mysticism for now, guess you had
> enough of that in your meeting with Wheeler) discusses this in (click
> on cpp.pdf, type ctrl-f, type in "pseudo constructor", nope, remember
> that it is really cast notation, check §5.4, referred to §5.2.3 by
> §5.4/2) §5.2.3/1 "Explicit type conversion (functional notation)".[/color]

Oops, forgot, that's just part of the "pseudo constructor" thing that
makes it seem like scalar types have constructors. The part you're
actually asking about with your example is the initialization syntax
in declarations. And that's called a "direct-initialization" and
is partially covered by §8.5 and by §12.3/1. So a "pseudo constructor",
which is not named as such in the standard, is a concept implemented
by a little bit here and a little bit there, sort of well hidden... ;-)

Possibly there are even more small bits scattered here & there, but the
main point is that it's a trivial concept (make it seem like those types
have constructors) implemented piecemeal here and there because of the
way the structure of the standard turned out as a collaborative design.
If the standard were a computer program we'd refactor it. But with the
standard that would probably break too many references.

Now, hope this helps _this_ time...

--
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail?

"Steven T. Hatton" <susudata@setidava.kushan.aa> wrote[color=blue]
>
> [more snipping than you can shake a stick at]
>
> Here's the question. Where (how) does the Holy Standard
> specify that I can do this:
>
> int main(int argc, char* argv[]) {
> int i(3); // <---<---
> std::cout <<"i = " < }[/color]

8.5 (Initializers):

initializer:
= initializer clause
( expression-list )

.... and so on.

Claudio Puviani

On Sun, 04 Apr 2004 15:11:38 GMT, alfps@start.no (Alf P. Steinbach) wrote:
[color=blue]
>Oops, forgot, that's just part of the "pseudo constructor" thing that
>makes it seem like scalar types have constructors. The part you're
>actually asking about with your example is the initialization syntax
>in declarations. And that's called a "direct-initialization" and
>is partially covered by §8.5 and by §12.3/1. So a "pseudo constructor",
>which is not named as such in the standard, is a concept implemented
>by a little bit here and a little bit there, sort of well hidden... ;-)
>
>Possibly there are even more small bits scattered here & there, but the
>main point is that it's a trivial concept (make it seem like those types
>have constructors) implemented piecemeal here and there because of the
>way the structure of the standard turned out as a collaborative design.[/color]

It may be worth noting here that the use of pseudo-constructor syntax on
primitive types is what allows some templates to be written so that they
can be specialized for class /or/ primitive types. I'm not sure whether it
would be totally impossible, or just really ugly, without them.
-leor

--
Leor Zolman --- BD Software --- www.bdsoft.com
On-Site Training in C/C++, Java, Perl and Unix
C++ users: Download BD Software's free STL Error Message Decryptor at:
www.bdsoft.com/tools/stlfilt.html

* alfps@start.no (Alf P. Steinbach) schriebt:[color=blue]
> * "Steven T. Hatton" <susudata@setidava.kushan.aa> schriebt:[color=green]
> > Here's the question. Where (how) does the Holy Standard specify that I can
> > do this:
> >
> > int main(int argc, char* argv[]) {
> > int i(3); // <---<---
> > std::cout <<"i = " < > }[/color]
>
> Well that's another thing entirely. That's a "pseudo constructor
> call". There's also "pseudo destructor call", but leave that for
> the moment.
>
> The standard (I'll leave off the mysticism for now, guess you had
> enough of that in your meeting with Wheeler) discusses this in (click
> on cpp.pdf, type ctrl-f, type in "pseudo constructor", nope, remember
> that it is really cast notation, check §5.4, referred to §5.2.3 by
> §5.4/2) §5.2.3/1 "Explicit type conversion (functional notation)".[/color]

Oops, forgot, that's just part of the "pseudo constructor" thing that
makes it seem like scalar types have constructors. The part you're
actually asking about with your example is the initialization syntax
in declarations. And that's called a "direct-initialization" and
is partially covered by §8.5 and by §12.3/1. So a "pseudo constructor",
which is not named as such in the standard, is a concept implemented
by a little bit here and a little bit there, sort of well hidden... ;-)

Possibly there are even more small bits scattered here & there, but the
main point is that it's a trivial concept (make it seem like those types
have constructors) implemented piecemeal here and there because of the
way the structure of the standard turned out as a collaborative design.
If the standard were a computer program we'd refactor it. But with the
standard that would probably break too many references.

Now, hope this helps _this_ time...

--
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail?

On Sun, 04 Apr 2004 15:11:38 GMT, alfps@start.no (Alf P. Steinbach) wrote:
[color=blue]
>Oops, forgot, that's just part of the "pseudo constructor" thing that
>makes it seem like scalar types have constructors. The part you're
>actually asking about with your example is the initialization syntax
>in declarations. And that's called a "direct-initialization" and
>is partially covered by §8.5 and by §12.3/1. So a "pseudo constructor",
>which is not named as such in the standard, is a concept implemented
>by a little bit here and a little bit there, sort of well hidden... ;-)
>
>Possibly there are even more small bits scattered here & there, but the
>main point is that it's a trivial concept (make it seem like those types
>have constructors) implemented piecemeal here and there because of the
>way the structure of the standard turned out as a collaborative design.[/color]

It may be worth noting here that the use of pseudo-constructor syntax on
primitive types is what allows some templates to be written so that they
can be specialized for class /or/ primitive types. I'm not sure whether it
would be totally impossible, or just really ugly, without them.
-leor

--
Leor Zolman --- BD Software --- www.bdsoft.com
On-Site Training in C/C++, Java, Perl and Unix
C++ users: Download BD Software's free STL Error Message Decryptor at:
www.bdsoft.com/tools/stlfilt.html

Alf P. Steinbach wrote:
[color=blue]
> Oops, forgot, that's just part of the "pseudo constructor" thing that
> makes it seem like scalar types have constructors. The part you're
> actually asking about with your example is the initialization syntax
> in declarations. And that's called a "direct-initialization" and
> is partially covered by §8.5 and by §12.3/1. So a "pseudo constructor",
> which is not named as such in the standard, is a concept implemented
> by a little bit here and a little bit there, sort of well hidden... ;-)
>
> Possibly there are even more small bits scattered here & there, but the
> main point is that it's a trivial concept (make it seem like those types
> have constructors) implemented piecemeal here and there because of the
> way the structure of the standard turned out as a collaborative design.
> If the standard were a computer program we'd refactor it. But with the
> standard that would probably break too many references.[/color]

I was wondering what a spaghetti diagram might look like. The Standard is
organized in a hierarchical structure using symbols such as [basic],
[basic.def],[basic.def.odr], etc.

http://www.itga.com.au/~gnb/wp/cd2/

There are extensive crossreferences pointing to different sections. I
wonder what it would look like if someone tried to pin it all up on a huge
tack board with lines connecting the references. Could it be treated as a
collection of objects in some kind of (pseudo-) UML diagram? It might also
be instructive to include the grammar in this spaghetti diagram.

Another thing that might be useful is a hyperlinked version of the Grammar
which took the user to discussion in the text, and/or examples using the
particular derivation.
[color=blue]
> Now, hope this helps _this_ time...[/color]

I'll have to review it all. Parts of the Standard are very hard to read
because they have a lot of forward references (if that's the proper term
for things mentioned but not yet defined). Other parts are easier to read
than TC++PL(SE) discussion of the same topic. I'm currently trying to slog
my way through Clause(?) 3 [basic]. The whole 'chapter'.

--
p->m == (*p).m == p[0].m
http://www.kdevelop.org
http://www.suse.com
http://www.mozilla.org

Alf P. Steinbach wrote:
[color=blue]
> Oops, forgot, that's just part of the "pseudo constructor" thing that
> makes it seem like scalar types have constructors. The part you're
> actually asking about with your example is the initialization syntax
> in declarations. And that's called a "direct-initialization" and
> is partially covered by §8.5 and by §12.3/1. So a "pseudo constructor",
> which is not named as such in the standard, is a concept implemented
> by a little bit here and a little bit there, sort of well hidden... ;-)
>
> Possibly there are even more small bits scattered here & there, but the
> main point is that it's a trivial concept (make it seem like those types
> have constructors) implemented piecemeal here and there because of the
> way the structure of the standard turned out as a collaborative design.
> If the standard were a computer program we'd refactor it. But with the
> standard that would probably break too many references.[/color]

I was wondering what a spaghetti diagram might look like. The Standard is
organized in a hierarchical structure using symbols such as [basic],
[basic.def],[basic.def.odr], etc.

http://www.itga.com.au/~gnb/wp/cd2/

There are extensive crossreferences pointing to different sections. I
wonder what it would look like if someone tried to pin it all up on a huge
tack board with lines connecting the references. Could it be treated as a
collection of objects in some kind of (pseudo-) UML diagram? It might also
be instructive to include the grammar in this spaghetti diagram.

Another thing that might be useful is a hyperlinked version of the Grammar
which took the user to discussion in the text, and/or examples using the
particular derivation.
[color=blue]
> Now, hope this helps _this_ time...[/color]

I'll have to review it all. Parts of the Standard are very hard to read
because they have a lot of forward references (if that's the proper term
for things mentioned but not yet defined). Other parts are easier to read
than TC++PL(SE) discussion of the same topic. I'm currently trying to slog
my way through Clause(?) 3 [basic]. The whole 'chapter'.

--
p->m == (*p).m == p[0].m
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initialization vs assignment

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re: initialization vs assignment

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re: initialization vs assignment

re: initialization vs assignment

re: initialization vs assignment

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re: initialization vs assignment

re: initialization vs assignment

re: initialization vs assignment

Similar C / C++ bytes

/bytes/development

/bytes/it

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