Edit report at https://bugs.php.net/bug.php?id=61954&edit=1
ID: 61954
Comment by: anon at anon dot anon
Reported by: dm at dmillerweb dot com
Summary: Multi-CASE line for SWITCH
Status: Open
Type: Feature/Change Request
Package: *General Issues
Operating System: N/A
PHP Version: 5.4.2
Block user comment: N
Private report: N
New Comment:
Several other languages do support fancier rules in their switch statements,
though. One variant of the B language (B being the language which first devised
the current syntax for the switch statement) allowed ranges such as "case 1 ::
10" and comparisons such as "case >= 5". Most BASICs allow ranges ("CASE 1 TO
10"), comparisons ("CASE IS < 5"), and comma-separated values ("CASE 2, 4, 6").
Ruby allows comma separated values ("when 2, 4, 6") and ranges ("when 1..10").
It would be useful if PHP supported some of those features.
Previous Comments:
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[2012-05-05 21:45:02] anon at anon dot anon
The standard way to accept multiple case values (in all C-like languages,
including PHP) is to put multiple case labels. It's not quite as succinct as
your example, but it does fulfill the purpose of allowing you to only write the
handlers once:
switch ($color) {
case "blue":
case "green":
case "aqua":
echo $color . " is a cool color.";
break;
case "red": case "orange": case "brown":
echo $color . " is a warm color.";
break;
}
Adding { } around those sections is actually already valid syntax, though in
PHP it does nothing because PHP doesn't have block scope
(https://en.wikipedia.org/wiki/Scope_%28computer_science%29#Block_scope_within_a_function).
In some similar languages, that syntax delimits a scope but doesn't imply a
"break;", so PHP could only add that new logic if it's willing to confuse
people. It would also break backwards compatibility with any odd code that
already has extra { } in its switch handlers.
------------------------------------------------------------------------
[2012-05-05 20:23:47] dm at dmillerweb dot com
Description:
------------
---
>From manual page: http://www.php.net/control-structures.switch
---
I did not see this capability on the manual page, so please forgive me if such
an improvement is already in the works.
I believe it would be a great help to upgrade the SWITCH -> CASE statements so
they accept multiple values. This would allow us to write only one block of
code-to-be-executed even for multiple values.
Here's an example:
switch ($color) {
case: "blue", "green", "aqua"
echo $color . " is a cool color."
break;
case: "red", "orange", "brown"
echo $color . " is a warm color."
}
Also, we could eliminate the need for the BREAK statement by allowing code
after the CASE statement to be enclosed in braces; the closing brace for that
code would indicate an automatic BREAK.
Hope this helps.
David Miller
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