Perl: Call function using a variable

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You can call a Perl function using a variable. For example below code, here the variable $perl_function_name whose value is "call_function", you can call the function as &$perl_function_name() instead of calling call_function();
my $perl_function_name = "call_function";

## calling without parameter passing
&$perl_function_name();

## calling with parameter passing
&$perl_function_name(10);

## example function
sub call_function{
    my $param = shift;
    if($param){
        print "Calling function using variable with parameter $param\n";
    }
    else{
        print "Calling function using variable\n";
    }
}
Using the 'use strict;' I found the code doesn't work. The error i got Can't use string ("call_function") as a subroutine ref while "strict refs" in use Anyone knows why? Or any other way to do this?

For more Perl you can take a look at here http://icfun.blogspot.com/search/label/perl

Comments

Nick Morrisson said…
You can get use strict by doing:

use strict;
no strict "refs";

Check out the docs, though, as this does have other effects.
October 8, 2008 at 3:44 PM
David said…
Another option is to use eval

eval{ &$perl_function_name(10)} ;

This will work only in run time, and you wouldn't need to use

no strict "refs";
October 22, 2008 at 7:03 PM
Anonymous said…
how to do this when calling a function on an object ?
August 19, 2010 at 2:22 AM
Jon Hermansen said…
I'm also interested to know how to accomplish this when calling a function of an object.
November 18, 2010 at 2:21 PM
Farmboy said…
Methods are called the same way: $obj->$name(...). Using eval with braces does not work. The safest and most efficient way is to scope the no strict "refs" to the call only:

{
no strict "refs";
$obj->$name(...);
}
April 1, 2011 at 7:14 AM
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