Given that UNIX, including networking, is almost entirely coded in C,
how come so many things are almost impossible in ordinary C? Examples:
Network and internet access, access to UNIX interprocess controls and
communication, locale determination, EBCDIC/ASCII discrimination, etc.
Almost all of these are easy in Perl. Why isn't there a mechanism like
perl modules to allow easy extentions for facilities like these? Isn't
anyone working on this problem? or is it all being left for proprietary
systems?
Sep 2 '08
223  7384 
jacob navia wrote:
>
I consider C++ a very complex language where bugs have a lot more
places to hide.
While it is complex, it offers bigger hammers to squash bugs!
Like many new toys, C++ adds the tools to eliminate common C bugs, while
introducing plenty of scope for bugs of its own.
--
Ian Collins.
REH wrote:
On Sep 6, 1:44 pm, jacob navia <ja...@nospam.c omwrote:
>TYPE operator [ ]=(TYPE table, int idx, ELEMENT_TYPE newvalue)
This would apply to
table[idx] = newvalue;
In C++ there is no way to distinguish between those
operations since you just return a pointer.
This is done to support read only data types, what is very hard in C++.
nonsense.
Read:
const TYPE& operator[](std::size_t i) const;
or, if you prefer by value:
TYPE operator[](std::size_t i) const;
Write:
TYPE& operator[](std::size_t i);
x = y[1]; would call the operator with the read prototype.
y[1] = x; would call the operator with the write prototype.
No you are wrong there. Ask why on c.l.c++.
--
Ian Collins.
jacob navia wrote, On 09/09/08 00:14:
Flash Gordon wrote:
>Anand Hariharan wrote, On 08/09/08 16:19:
>>On Sep 4, 6:15 pm, Flash Gordon <s...@flash-gordon.me.ukwro te:
jacob navia wrote, On 04/09/08 00:08:
Because it is a *simple* language. Simple languages are easier to
understan d and use, and have less surface for bugs.
I've seen a lot of bugs in code written in simpler languages.
Could you elaborate? What are the mainstream programming languages
(as in those languages with a reasonable number of programs written
using them) that you consider to be simpler than C?
Depending on your definition of simpler, I have...
Z80 assembler. This is a nice fairly simple assembly language and I've
seen lots of bugs in code written in it. It certainly was mainstream
back when I started using it, and there are a lot of NSC800 processors
(the military equivalent with a few extra built-in peripherals) still
flying around.
Pascal. This is simpler in terms of being in general a higher level
language without OO (which Jacob considers complex, and not without
reason), and I've seen lots of bugs in Pascal.
Choose a definition of simple and I am sure I can find a language I've
used which meets that definition.
I did NOT say that C has no bugs. Read what I wrote again:
Read what I said again. I said "lots".
>>jacob navia wrote, On 04/09/08 00:08:
>>>Simple languages are easier to
>>>understand and use, and have less surface for bugs.
Is that clear to you now?
"Less surface" means that, less surface, not NO bugs but fewer and
easier to find.
My experience is that bugs are just as common and just as good at hiding
in code written in every language I have used.
I consider C++ a very complex language where bugs have a lot more
places to hide.
I don't have enough experience of C++ to comment about that. However, I
do have experience of "simpler" languages than C and my experience is
that the skill level of the people and the quality of the development
process have a far larger impact than the language on the bug count and
the difficulty in finding the bugs.
--
Flash Gordon
On 9 Sep, 00:14, jacob navia <ja...@nospam.c omwrote:
Flash Gordon wrote:
Anand Hariharan wrote, On 08/09/08 16:19:
On Sep 4, 6:15 pm, Flash Gordon <s...@flash-gordon.me.ukwro te:
jacob navia wrote, On 04/09/08 00:08:
>>Because [C] is a *simple* language. Simple languages are easier to
understand and use, and have less surface for bugs.
I dunno. You tend to have to write more code to do things that
a more "complex" language would express in less code.
Consider a C with operator over-loading. This is more both more
expressive and more complex than standard C. :-)
>I've seen a lot of bugs in code written in simpler languages.
Could you elaborate? *What are the mainstream programming languages
(as in those languages with a reasonable number of programs written
using them) that you consider to be simpler than C?
Depending on your definition of simpler, I have...
Z80 assembler. This is a nice fairly simple assembly language and I've
seen lots of bugs in code written in it. It certainly was mainstream
back when I started using it, and there are a lot of NSC800 processors
(the military equivalent with a few extra built-in peripherals) still
flying around.
Pascal. This is simpler in terms of being in general a higher level
language without OO (which Jacob considers complex, and not without
reason), and I've seen lots of bugs in Pascal.
Choose a definition of simple and I am sure I can find a language I've
used which meets that definition.
I did NOT say that C has no bugs. Read what I wrote again:
he didn't say you said...
*>>jacob navia wrote, On 04/09/08 00:08:
*>>>Simple languages are easier to
*>>>understand and use, and have less surface for bugs.
Is that clear to you now?
"Less surface" means that, less surface, not NO bugs but fewer and
easier to find.
um no. Since programming languages don't have surfaces they can't
have "less surface". It's a metaphor and you don't explain a metaphor
by, basically, repeating the metaphor.
One of my pet hates is things like "he was *literally* blown away".
Well
unless he was mishandling explosives, no he wasn't.
I consider C++ a very complex language where bugs have a lot more
places to hide.
how many places can this expression generate an exception?
a = b + c;
--
Nick Keighley
"If you think C++ is not overly complicated, just what is a protected
abstract virtual base pure virtual private destructor, and when
was the last time you needed one?"
-- Tom Cargil, C++ Journal.
Nick Keighley wrote:
Consider a C with operator over-loading. This is more both more
expressive and more complex than standard C. :-)
No, because standard C includes complex numbers. This extension would
make the language *smaller* because complex numbers could
be left *out* of the language itself, making it simpler
yet more powerful.
>"Less surface" means that, less surface, not NO bugs but fewer and
easier to find.
um no. Since programming languages don't have surfaces they can't
have "less surface". It's a metaphor and you don't explain a metaphor
by, basically, repeating the metaphor.
The "surface" of a language is the number of features exposed
to the user at any given time.
When you write in a simple language you can have all the features
of the language in your mind and you can know exactly what are you
doing.
When you write in a complex language, there are so many features
available that it is impossible for you to have all of them
in your mind when writing new code. There are then features that can
provoke bugs that you can't foresee.
>
--
Nick Keighley
"If you think C++ is not overly complicated, just what is a protected
abstract virtual base pure virtual private destructor, and when
was the last time you needed one?"
-- Tom Cargil, C++ Journal.
It is interesting that in your signature you quote a confirmation of
what I am arguing.
--
jacob navia
jacob at jacob point remcomp point fr
logiciels/informatique http://www.cs.virginia.edu/~lcc-win32
Flash Gordon wrote:
I don't have enough experience of C++ to comment about that. However, I
do have experience of "simpler" languages than C and my experience is
that the skill level of the people and the quality of the development
process have a far larger impact than the language on the bug count and
the difficulty in finding the bugs.
The problem with complicated/complex languages is that you just
can't have all the features of the language in your mind when writing
new code.
For instance I said in this same thread that C++ can't differentiate
with the overloaded '[' ']' operator between writing and reading.
Almost immediately, one C++ expert told me that is nonsense and
proposed a solution. The solution looks quite plausible, and nobody
objected (I was just waited).
A day later another expert says that the solution proposed by the
first expert will just not work. He said (to the first expert) that
he should ask in comp.lang.c++ why it doesn't work.
When I asked the same question in the C++ experts group, it took
quite a while until one expert proposed a solution that was
accepted by the others, maybe because involved templates and
was (as always in c++) an atomic bomb to kill a fly.
The problem with a language like that is that the interactions
among the million features are just *beyond* what a human
mind can follow.
The specifications for name lookup when following a class
overloaded operator are pages and pages, involving a
topological sort, etc. It is impossible for a human to
follow all that. Only a machine can have the patience to
do this kind of stuff.
At that point, a language becomes segmented in the programmer's
mind. He/she will concentrate on the features he/she assumes
that have relevance to the problem at hand and ignore the
possible subtle interactions of all the others.
You have to keep in mind that when writing code there are
TWO completely different "computers" involved:
(1): A "biological " computer made of billions of processors that
is NOT designed for programming
(2) a CPU
(1) is designed after around 1 billion years of evolution for
coping with a natural environment, where computers just
do not exist. It has a short attention span and a very
limited short term memory.
"To err is human", and the possibility of introducing errors in a
program increases with the number of features you have to keep
in mind.
--
jacob navia
jacob at jacob point remcomp point fr
logiciels/informatique http://www.cs.virginia.edu/~lcc-win32
On 9 Sep, 09:26, jacob navia <ja...@nospam.c omwrote:
Nick Keighley wrote:
Consider a C with operator over-loading. This is more both more
expressive and more complex than standard C. * :-)
No, because standard C includes complex numbers. This extension would
make the language *smaller* because complex numbers could
be left *out* of the language itself, making it simpler
yet more powerful.
a similar argument could be made for templates in C++
allowing the existence of the STL
<snip>
The "surface" of a language is the number of features exposed
to the user at any given time.
When you write in a simple language you can have all the features
of the language in your mind and you can know exactly what are you
doing.
When you write in a complex language, there are so many features
available that it is impossible for you to have all of them
in your mind when writing new code. There are then features that can
provoke bugs that you can't foresee.
--
Nick Keighley
"If you think C++ is not overly complicated, just what is a protected
*abstract virtual base pure virtual private destructor, and when
*was the last time you needed one?"
* * * * * * * * * *-- Tom Cargil, C++ Journal.
It is interesting that in your signature you quote a confirmation of
what I am arguing.
my sigs are not randomly generated
--
Nick Keighley
why isn't there an obfuscated C++ contest?
jacob navia <ja***@nospam.c omwrites:
Flash Gordon wrote:
>I don't have enough experience of C++ to comment about
that. However, I do have experience of "simpler" languages than C
and my experience is that the skill level of the people and the
quality of the development process have a far larger impact than the
language on the bug count and the difficulty in finding the bugs.
The problem with complicated/complex languages is that you just
can't have all the features of the language in your mind when writing
new code.
For instance I said in this same thread that C++ can't differentiate
with the overloaded '[' ']' operator between writing and reading.
Almost immediately, one C++ expert told me that is nonsense and
proposed a solution. The solution looks quite plausible, and nobody
objected (I was just waited).
A day later another expert says that the solution proposed by the
first expert will just not work. He said (to the first expert) that
he should ask in comp.lang.c++ why it doesn't work.
When I asked the same question in the C++ experts group, it took
quite a while until one expert proposed a solution that was
accepted by the others, maybe because involved templates and
was (as always in c++) an atomic bomb to kill a fly.
The problem with a language like that is that the interactions
among the million features are just *beyond* what a human
mind can follow.
Am I allowed here to say once more - and this is why operator
overloading is nonsense and leads to horrible, unmaintainable code?
I have worked with experts and language lawyers. And all they do is
argue about the cleverest way to do things. And Introducing Operator
Overloading into C will see a huge reduction in the quality and
maintainability of the code bases. Been there done that with C++.- Yes,
I know, "if done properly" - but listen to the experts argue about best
approach and then consider "average Ted" and what he would
do. Nope. Keep them away.
On Sep 9, 1:13*am, Ian Collins <ian-n...@hotmail.co mwrote:
REH wrote:
On Sep 6, 1:44 pm, jacob navia <ja...@nospam.c omwrote:
TYPE operator [ ]=(TYPE table, int idx, ELEMENT_TYPE newvalue)
This would apply to
* * * * table[idx] = newvalue;
In C++ there is no way to distinguish between those
operations since you just return a pointer.
This is done to support read only data types, what is very hard in C++..
nonsense.
Read:
const TYPE& operator[](std::size_t i) const;
or, if you prefer by value:
TYPE operator[](std::size_t i) const;
Write:
TYPE& operator[](std::size_t i);
x = y[1]; would call the operator with the read prototype.
y[1] = x; would call the operator with the write prototype.
No you are wrong there. *Ask why on c.l.c++.
--
Ian Collins.
Um, no I am not. I don't need to ask. I've been writing C++ code
before it even had a standard.
REH
jacob navia wrote:
>
For instance I said in this same thread that C++ can't differentiate
with the overloaded '[' ']' operator between writing and reading.
Almost immediately, one C++ expert told me that is nonsense and
proposed a solution. The solution looks quite plausible, and nobody
objected (I was just waited).
How do you define 'immediately' (almost 2 days) and how do you define
expert?
A day later another expert says that the solution proposed by the
first expert will just not work. He said (to the first expert) that
he should ask in comp.lang.c++ why it doesn't work.
Where else should the so called expert go to find the error of his ways?
Do all C programmers agree all of the time? A day or two here will
answer that.
When I asked the same question in the C++ experts group, it took
quite a while until one expert proposed a solution that was
accepted by the others, maybe because involved templates and
was (as always in c++) an atomic bomb to kill a fly.
Proxies are the idiomatic way to determine read from write. No
templates are required.
The problem with a language like that is that the interactions
among the million features are just *beyond* what a human
mind can follow.
Then use the ones your mind can follow, which is what most programmers
do in most languages. What I do like is a language that can solve
problems (such as determining read from write to an array) without
resorting to language extensions.
At that point, a language becomes segmented in the programmer's
mind. He/she will concentrate on the features he/she assumes
that have relevance to the problem at hand and ignore the
possible subtle interactions of all the others.
So all C programmers use all the dusty corners of the language? Most
programmers work in teams and the collective knowledge of the team helps
the individual's knowledge to grow.
--
Ian Collins. This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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