Hi internals
Looking through the language grammer I discovered that switch cases can also be terminated with a ; instead of a :.
switch ($i) {
case 1;
return 1;
default;
return 2;
}
This is in fact documented:
https://www.php.net/manual/en/control-structures.switch.php
What's the reasoning behind this? I find it weird an inconsistent.
Maybe something to deprecate in PHP 8.0.
https://wiki.php.net/rfc/deprecations_php_8_0
Regards
Hi!
Maybe something to deprecate in PHP 8.0.
https://wiki.php.net/rfc/deprecations_php_8_0
Why? Whose life it'd make easier?
--
Stas Malyshev
smalyshev@gmail.com
I agree with Tovilo. It is weird and confusing. Actually I never know that
it was possible. And the ";" sounds like "it ends here", while ":" counds
like "it does it ->". For me, "case 1;" will sounds like "skip case 1".
Atenciosamente,
David Rodrigues
Em qui., 26 de mar. de 2020 às 17:14, Stanislav Malyshev <
smalyshev@gmail.com> escreveu:
Hi!
Maybe something to deprecate in PHP 8.0.
https://wiki.php.net/rfc/deprecations_php_8_0Why? Whose life it'd make easier?
--
Stas Malyshev
smalyshev@gmail.com
Hi!
I agree with Tovilo. It is weird and confusing. Actually I never know
that it was possible.
You seem to contradict yourself - if you never knew it was possible, how
could you ever be confused by it?
--
Stas Malyshev
smalyshev@gmail.com
Le Thu, 26 Mar 2020 21:28:38 +0100, Stanislav Malyshev
smalyshev@gmail.com a écrit:
Hi!
I agree with Tovilo. It is weird and confusing. Actually I never know
that it was possible.You seem to contradict yourself - if you never knew it was possible, how
could you ever be confused by it?
OK, I'm often lurking, but I have to react to this. I never knew it was
possible too, but I am also confused by this. A semi-colon is terminal. It
always is. "You see this set of instructions? Done.". But in this case, it
is not. You see the problem?
--
L'absence de virus dans ce courrier électronique a été vérifiée par le logiciel antivirus Avast.
https://www.avast.com/antivirus
Le 26 mars 2020 à 21:49, Benoit SCHILDKNECHT bensor987@neuf.fr a écrit :
A semi-colon is terminal. Italways is. "You see this set of instructions? Done.". But in this case, itis not. You see the problem?
No I don’t see the problem. Inside a switch construct, when you reach the end of an instruction (or of a set of instructions) that is not (resp. does not end with) a control-flow statement, you pass to the next one. I’m sure that everybody knows that you have to use an explicit control-flow statement like “break” or “return” if you want to be “done” before reaching the bottom of the switch construct.
Or maybe people could misguess that “;” in that context is an odd way to mean “: break;”?
—Claude
Le 26 mars 2020 à 19:37, Ilija Tovilo ilija.tovilo@me.com a écrit :
What's the reasoning behind this? I find it weird an inconsistent.
This is a manifestly a leftover of an old syntax. Take a look at the PHP/FI 2 manual:
Language constructs:
https://www.php.net/manual/phpfi2.php#lang https://www.php.net/manual/phpfi2.php#lang
<?
if($a==5 && $b!=0 );
$c = 100 + $a / $b;
endif;
>
and, in particular, switch construct:
https://www.php.net/manual/phpfi2.php#switch https://www.php.net/manual/phpfi2.php#switch
<?
$a=0;
switch($a) {
case 1;
echo "a is 1";
break;
case "hello";
echo "a is hello";
break;
default;
echo "a is unknown";
break;
}
>
Note that every line of code, including if (...); and case...;, is consistently terminated by a semicolon.
In a subsequent major version, the syntax was modified, and you would use a colon instead of a semicolon in a number of places, as you can write today:
<?php
if ($a==5 && $b!=0):
$c = 100 + $a / $b;
endif;
>
Although the old if (true); syntax has been removed (probably because of ambiguity or difficulty of parsing), the old case 1; syntax could be left without issue.
—Claude
Le 26 mars 2020 à 19:37, Ilija Tovilo ilija.tovilo@me.com a écrit :
What's the reasoning behind this? I find it weird an inconsistent.
This is a manifestly a leftover of an old syntax. Take a look at the PHP/FI 2 manual:
Language constructs:
https://www.php.net/manual/phpfi2.php#lang https://www.php.net/manual/phpfi2.php#lang<? if($a==5 && $b!=0 ); $c = 100 + $a / $b; endif; >and, in particular, switch construct:
https://www.php.net/manual/phpfi2.php#switch https://www.php.net/manual/phpfi2.php#switch<? $a=0; switch($a) { case 1; echo "a is 1"; break; case "hello"; echo "a is hello"; break; default; echo "a is unknown"; break; } >Note that every line of code, including
if (...);andcase...;, is consistently terminated by a semicolon.In a subsequent major version, the syntax was modified, and you would use a colon instead of a semicolon in a number of places, as you can write today:
<?php if ($a==5 && $b!=0): $c = 100 + $a / $b; endif; >Although the old
if (true);syntax has been removed (probably because of ambiguity or difficulty of parsing), the oldcase 1;syntax could be left without issue.
Interesting! Thanks for digging this out. :)
--
Christoph M. Becker
Hi Ilija,
Ilija Tovilo wrote:
Looking through the language grammer I discovered that switch cases can also be terminated with a
;instead of a:.switch ($i) { case 1; return 1; default; return 2; }This is in fact documented:
https://www.php.net/manual/en/control-structures.switch.phpWhat's the reasoning behind this? I find it weird an inconsistent.
For whatever reason, I somehow remember that this dates to at least
PHP/FI 2.0, which means it's as least as old as me (24 years… no, I was
not involved with PHP back then ;). And indeed, the case statement is
mentioned in the manual (https://www.php.net/manual/phpfi2.php#lang),
with an example to be found in
https://museum.php.net/php2/php-2.0.tar.gz under php-2.0/test/lang/003.tst:
--TEST--
Simple Switch Test ...
--POST--
--GET--
--FILE--
<?$a=1;
switch($a);
case 0;
echo "bad";
break;
case 1;
echo "good";
break;
default;
echo "bad";
break;
endswitch>
--EXPECT--
Content-type: text/html
good
Being able to use a colon instead of a semicolon here is, I guess, a
more modern thing. Was it PHP 3 or PHP 4 that changed this? Who knows.
I don't think it's hurting anyone as it is… can we leave it in peace? :)
Thanks,
Andrea