I have been away for the longest time and happened on this comment today.

A bigger issue is using &subname to call subs instead of subname() - that really doesn't do what you think it does. - in this thread Re: What to use instead of global variables

So I wondered what the difference was. I wrote the following as a SIMPLE test to see if anything jumped out at me.

#!/usr/bin/perl

use strict;
use warnings;

print "About to test sub calls using \& --\n";
&test1;

print "About to test sub call using name() --\n";
test2();

sub test1() {
    print "test1: Working\n";
}

sub test2() {
    print "test2: Working\n";
}

[download]

When I do a "perl -c myScript.pl" I get the following

main::test2() called too early to check prototype at myScript.pl line 10. myScript.pl syntax OK

And when I run the script it seems to work with no problems. Other than I get the same warning and in the syntax check before the output. Now I do realise that I could simply remove the use warnings; from my script but I was wondering -

  1. What is the warning telling me?
  2. Also what is the difference between calling a function using &subname or subname()
  3. Where in the manual can I RTFM?
  4. Perhaps an simple example showing the different scenarios for using the different ways of calling the function


Of all the things I've lost in my life, its my mind I miss the most.

In reply to Calling Functions by AcidHawk

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