Re: How to call subroutines using variables ?

I agree with Joost, you should probably use function references as he suggests. However, there's a couple ways to do what you want if you are stuck with a value that is a function name. Cheap way 1:

eval "&$s()";
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Or you could try:

&{ &UNIVERSAL::can('main', $s) }();
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To rewrite the second example to make it nicer:

my $funcRef = &UNIVERSAL::can('main', $s);
if( ref($funcRef) eq 'CODE' ) { &$funcRef(); }
else { warn "Function $s not found in package main!"; }
[download]

(update: should probably check the return from 'can' to ensure it returns a function reference)

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Re^2: How to call subroutines using variables ? by Joost (Canon) on Mar 22, 2007 at 23:10 UTC
eval "&$s()"; Oof. Don't do that. It's a lot safer to turn of strict refs instead: `no strict 'refs'; $s->(); use strict;` [download] That should still be treated with care, though. It will run ANY subroutine (even in other packages) that can be reached by name. Using your eval STRING option will run ANY code that happens to be in $s. Like: `$s = "print(); unlink '/etc/passwd'; s";` [download] updated: fixed quoting "What should it profit a man, if he should win a flame war, yet lose his cool?"	[reply] [d/l] [select]
Re^3: How to call subroutines using variables ? by Anonymous Monk on Aug 13, 2007 at 20:49 UTC
what if function $s is defined another perl module. Even though i include the perl module .I get this error Undefined subroutine &main::hello	[reply]
Re^4: How to call subroutines using variables ? by Joost (Canon) on Aug 13, 2007 at 20:52 UTC
Use the full package name, if you MUST use symbolic references: `my $ref = "SomePackage::Name::subname"; $ref->(@arguments);` [download] "What should it profit a man, if he should win a flame war, yet lose his cool?"	[reply] [d/l]
Re^2: How to call subroutines using variables ? by chromatic (Archbishop) on Mar 23, 2007 at 05:20 UTC
It's a lot cleaner to use: `my $func_ref = main->can( $s );` Checking that `$func_ref` is true should be sufficient. (Checking ref doesn't always work.)	[reply] [d/l] [select]