Assigning variables in if's

[jodleren]

Hi!

In while (false !== ($file = readdir($handle)))

what happens?
The $file gets assigned, and the value of that is compared with false?
The assignment is being compared with false

Say, I want to return true or an error code. Can I do;

if($err = somefunc())
echo "ok"
else
echo "error: $err";

WBR
Sonnich

[Captain Paralytic]

On 28 Nov, 09:24, jodleren <[e-mail]:

Hi!

In while (false !== ($file = readdir($handle)))

what happens?
The $file gets assigned, and the value of that is compared with false?
The assignment is being compared with false

Say, I want to return true or an error code. Can I do;

if($err = somefunc())
echo "ok"
else
echo "error: $err";

WBR
Sonnich

if($err = somefunc())
echo "ok"
else
echo "error: $err";

may work.

An assignment "returns" the value that was assigned. This is why you
can do:

$a = $b = $c = 5;

and all 3 variables will have the value 5.

In your "if" comparison, any non-empty or non-zero value in the
brackets will be taken to be true.

So, if somefunc() returns 0 or nothing for a good result, then your
statement will do what you want.

[jodleren]

On Nov 28, 12:35 pm, Captain Paralytic <[e-mail]:

On 28 Nov, 09:24, jodleren <[e-mail]:

Hi!

In while (false !== ($file = readdir($handle)))

what happens?
The $file gets assigned, and the value of that is compared with false?
The assignment is being compared with false

Say, I want to return true or an error code. Can I do;

if($err = somefunc())
echo "ok"
else
echo "error: $err";

WBR
Sonnich

if($err = somefunc())
echo "ok"
else
echo "error: $err";

may work.

An assignment "returns" the value that was assigned. This is why you
can do:

$a = $b = $c = 5;

and all 3 variables will have the value 5.

In your "if" comparison, any non-empty or non-zero value in the
brackets will be taken to be true.

So, if somefunc() returns 0 or nothing for a good result, then your
statement will do what you want.- Hide quoted text -

- Show quoted text -

If found, that it does not work, so I ended up using this

$err = somefunc();
if($err===true)
echo "ok"
else
echo "error: $err";

and probably I'll change it to return 0 as no error.

WBR
Sonnich

[Toby A Inkster]

jodleren wrote:

$err = somefunc();
if($err===true)
echo "ok"
else
echo "error: $err";

echo (true === ($err = somefunc())) ? 'ok' : "error: $err";

:-)

--
Toby A Inkster BSc (Hons) ARCS
[Geek of HTML/SQL/Perl/PHP/Python/Apache/Linux]
[OS: Linux 2.6.17.14-mm-desktop-9mdvsmp, up 4 days, 17:00.]
[Now Playing: Counting Crows - Walkaways]

Sharing Music with Apple iTunes
http://tobyinkster.co.uk/blog/2007/1...tunes-sharing/

[taps128]

Toby A Inkster wrote:

jodleren wrote:

>$err = somefunc();
if($err===true)
echo "ok"
else
echo "error: $err";

echo (true === ($err = somefunc())) ? 'ok' : "error: $err";

:-)

or more readable(to me) IMHO
$err=foo();
switch($err){
case true: echo 'ok';break;
case false: echo 'error: '.$err;
}

But of course thats just a matter of style.

[Jerry Stuckle]

taps128 wrote:

Toby A Inkster wrote:

>jodleren wrote:

>>$err = somefunc();
if($err===true)
echo "ok"
else
echo "error: $err";

echo (true === ($err = somefunc())) ? 'ok' : "error: $err";

:-)

or more readable(to me) IMHO
$err=foo();
switch($err){
case true: echo 'ok';break;
case false: echo 'error: '.$err;
}

But of course thats just a matter of style.

More than a matter of style. If the function returns '1', your way will
print 'ok', while Toby's function will return the more correct 'error: 1'.

--
==================
Remove the "x" from my email address
Jerry Stuckle
JDS Computer Training Corp.
js*******@attglobal.net
==================

[Toby A Inkster]

taps128 wrote:

or more readable(to me)

Readable perhaps, but boring. echo (true === ($err = somefunc())) ? 'ok' :
"error: $err"; is fun. It invites the reader to explore its mysteries; to
embark in a journey of discovery, a quest filled with a sense of awe and
wonder. And in a sense it helps the reader to uncover new things about
*themselves* and unfold the secrets of their very souls.

Plus it saves almost 30 bytes.

--
Toby A Inkster BSc (Hons) ARCS
[Geek of HTML/SQL/Perl/PHP/Python/Apache/Linux]
[OS: Linux 2.6.17.14-mm-desktop-9mdvsmp, up 4 days, 20:07.]
[Now Playing: Keane - On a Day like Today]

Sharing Music with Apple iTunes
http://tobyinkster.co.uk/blog/2007/1...tunes-sharing/

[Pavel Lepin]

Toby A Inkster <us**********@tobyinkster.co.ukwrote in
<p0************@ophelia.g5n.co.uk>:

taps128 wrote:

>or more readable(to me)

Readable perhaps, but boring. echo (true === ($err =
somefunc())) ? 'ok' : "error: $err"; is fun. It invites
the reader to explore its mysteries; to embark in a
journey of discovery, a quest filled with a sense of awe
and wonder.

This particular example is very, very mild, and would be
just fine with me, but as a general rule, fun code invites
the code reviewer to explore the mysteries of the
commiter's entrails. The reason for that is that when we
need something done, journey of discovery is the last thing
we want, especially if we can only spare the least
experienced member of the team to work on the task at hand.

Plus it saves almost 30 bytes.

Whoa, groovy. It's, like, gonna save seven and a half baby
seals due to its, like, sheer, mind-boggling environment
friendliness.

--
....also, I submit that we all must honourably commit seppuku
right now rather than serve the Dark Side by producing the
HTML 5 spec.

[Gordon]

On Nov 29, 1:22 pm, Toby A Inkster <[e-mail]>
wrote:

taps128 wrote:

or more readable(to me)

Readable perhaps, but boring. echo (true === ($err = somefunc())) ? 'ok' :
"error: $err"; is fun. It invites the reader to explore its mysteries; to
embark in a journey of discovery, a quest filled with a sense of awe and
wonder. And in a sense it helps the reader to uncover new things about
*themselves* and unfold the secrets of their very souls.

Plus it saves almost 30 bytes.

--
Toby A Inkster BSc (Hons) ARCS
[Geek of HTML/SQL/Perl/PHP/Python/Apache/Linux]
[OS: Linux 2.6.17.14-mm-desktop-9mdvsmp, up 4 days, 20:07.]
[Now Playing: Keane - On a Day like Today]

Sharing Music with Apple iTunes
http://tobyinkster.co.uk/blog/2007/1...tunes-sharing/

And is completely contrary to the principles of writing maintainable
code. :) What code does should be self-evident, or at least self-
explanatory and well commented, because the poor sod who has to look
at the code in 18 months time to figure out why it's not behaving as
intended might be you.

[Jerry Stuckle]

Gordon wrote:

On Nov 29, 1:22 pm, Toby A Inkster <[e-mail]>
wrote:

>taps128 wrote:

>>or more readable(to me)

Readable perhaps, but boring. echo (true === ($err = somefunc())) ? 'ok' :
"error: $err"; is fun. It invites the reader to explore its mysteries; to
embark in a journey of discovery, a quest filled with a sense of awe and
wonder. And in a sense it helps the reader to uncover new things about
*themselves* and unfold the secrets of their very souls.

Plus it saves almost 30 bytes.

--
Toby A Inkster BSc (Hons) ARCS
[Geek of HTML/SQL/Perl/PHP/Python/Apache/Linux]
[OS: Linux 2.6.17.14-mm-desktop-9mdvsmp, up 4 days, 20:07.]
[Now Playing: Keane - On a Day like Today]

Sharing Music with Apple iTunes
http://tobyinkster.co.uk/blog/2007/1...tunes-sharing/

And is completely contrary to the principles of writing maintainable
code. :) What code does should be self-evident, or at least self-
explanatory and well commented, because the poor sod who has to look
at the code in 18 months time to figure out why it's not behaving as
intended might be you.

That is very true, and it depends on who's going to be reading it.

For instance, experienced C/C++ programmers would understand what it's
doing, even if they don't know PHP. However, a Perl programmer would be
more confused.

--
==================
Remove the "x" from my email address
Jerry Stuckle
JDS Computer Training Corp.
js*******@attglobal.net
==================

[taps128]

Jerry Stuckle wrote:

taps128 wrote:

>Toby A Inkster wrote:

>>jodleren wrote:

$err = somefunc();
if($err===true)
echo "ok"
else
echo "error: $err";

echo (true === ($err = somefunc())) ? 'ok' : "error: $err";

:-)

or more readable(to me) IMHO
$err=foo();
switch($err){
case true: echo 'ok';break;
case false: echo 'error: '.$err;
}

But of course thats just a matter of style.

More than a matter of style. If the function returns '1', your way will
print 'ok', while Toby's function will return the more correct 'error: 1'.

You right, i missed those '==='

[Michael]

Gordon wrote:

On Nov 29, 1:22 pm, Toby A Inkster <[e-mail]>
wrote:

>taps128 wrote:

>>or more readable(to me)

Readable perhaps, but boring. echo (true === ($err = somefunc())) ? 'ok' :
"error: $err"; is fun. It invites the reader to explore its mysteries; to
embark in a journey of discovery, a quest filled with a sense of awe and
wonder. And in a sense it helps the reader to uncover new things about
*themselves* and unfold the secrets of their very souls.

Plus it saves almost 30 bytes.

--
Toby A Inkster BSc (Hons) ARCS
[Geek of HTML/SQL/Perl/PHP/Python/Apache/Linux]
[OS: Linux 2.6.17.14-mm-desktop-9mdvsmp, up 4 days, 20:07.]
[Now Playing: Keane - On a Day like Today]

Sharing Music with Apple iTunes
http://tobyinkster.co.uk/blog/2007/1...tunes-sharing/

And is completely contrary to the principles of writing maintainable
code. :) What code does should be self-evident, or at least self-
explanatory and well commented, because the poor sod who has to look
at the code in 18 months time to figure out why it's not behaving as
intended might be you.

The ternary operator should not be 'confusing' to any competent PHP
programmer. Don't just leave out the parts that "Aren't your style".
Because you will come unstuck one day, when you don't understand
something that is normal and quite common.

besides,
echo(true===$e=somefunc())?'ok':"error: $e";

saves even more bytes ;)

- Michael

[Tim Roberts]

Toby A Inkster <us**********@tobyinkster.co.ukwrote:

>
Readable perhaps, but boring. echo (true === ($err = somefunc())) ? 'ok' :
"error: $err"; is fun. It invites the reader to explore its mysteries; to
embark in a journey of discovery, a quest filled with a sense of awe and
wonder. And in a sense it helps the reader to uncover new things about
*themselves* and unfold the secrets of their very souls.

+1 QOTW

I have to write that down. That has to be both the best and the worst
justification for obfuscated code that I've ever read.
--
Tim Roberts, ti**@probo.com
Providenza & Boekelheide, Inc.