#48192 [Opn]: if structure inherit else
ID: 48192
User updated by: skds1433 at hotmail dot com
Reported By: skds1433 at hotmail dot com
Status: Open
Bug Type: Feature/Change Request
Operating System: vista
PHP Version: 5.2.9
New Comment:
To me, the whole 'dangling else' is a paradox.
Wouldn't it seem more complete if that dangling 'else' was interpreted
for both 'if'?
If 'if a then if b then s1 else s2' was interpreted like this (below),
I personally see no paradox. It just seems to me, like a paradox for the
fact that this isn't how it's interpreted.
if (a)
{
if (b)
{
s1
}
else
{
s2
}
}
else
{
s2
}
I'm not looking for a solution, since there's probably 20 different
ways to solve that. I'm just suggesting what might be a better way.
Previous Comments:
------------------------------------------------------------------------
[2009-05-08 18:39:20] random-passer-by at hello dot world
This is a twist on the Dangling Else problem:
http://en.wikipedia.org/wiki/Dangling_else
I find your solution more confusing and incompatible than what I've
seen in any other other programming language.
This should achieve the correct result and avoid the extra foo
comparisons without a language change:
function routine ($foo, $bar)
{
do {
if ($foo === 0) { echo "foo is 0\n"; break; }
elseif ($foo === 1)
if ($bar === 0) { echo "bar is 0\n"; break; }
elseif ($bar === 1) { echo "bar is 1\n"; break; }
echo "foo: ".$foo.", bar: ".$bar."\n";
} while (0);
}
------------------------------------------------------------------------
[2009-05-08 17:04:59] skds1433 at hotmail dot com
Description:
------------
I'm requesting a way for the 'if' control struction to be able to
inherit 'else' control structures, in a similar matter as below. This
will help prevent duplicated code, and help keep it clean and
uncluttered.
I've included an 'expected_equivalent', which is actually less code
than in the 'routine' function. However, if a developer wishes to
include a greater diveristy, it can become a real advantage to use just
one 'else'.
Additionally, it I think it would be benefitional for 'if' control
structure to make it more 'complete'.
I also understand there are already numerous ways to do this, which
have the same result and possibly even less code. Nonetheless, I believe
this way could be a better, easier way for certain situations.
Reproduce code:
---------------
<?php
function routine ($foo, $bar)
{
if ($foo === 0) echo "foo is 0\n";
elseif ($foo === 1)
if ($bar === 0) echo "bar is 0\n";
elseif ($bar === 1) echo "bar is 1\n";
else echo "foo: ".$foo.", bar: ".$bar."\n";
# else would apply to both elseif
}
function expected_equivalent ($foo, $bar)
{
if ($foo === 0) echo "foo is 0\n";
elseif ($foo === 1 && $bar === 0) echo "bar is 0\n";
elseif ($foo === 1 && $bar === 1) echo "bar is 1\n";
else echo "foo: ".$foo.", bar: ".$bar."\n";
}
routine (0, 1);
routine (1, 0);
routine (1, 1);
routine (2, 1);
routine (1, 2);
routine (2, 2);
?>
Expected result:
----------------
foo is 0
bar is 0
bar is 1
foo: 2, bar: 1
foo: 1, bar: 2
foo: 2, bar: 2
Actual result:
--------------
foo is 0
bar is 0
bar is 1
foo: 1, bar: 2
------------------------------------------------------------------------
--
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