I have run into an odd corner of Perl behaviour I don't understand. I've simplified it down to the following snippet:

#! /usr/local/bin/perl -w

use strict;

sub one {1}
sub two {2}

sub three { one + two }
print three, "\n"; # outputs 1

sub really_three { one() + two }
print really_three, "\n"; # outputs 3

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I don't understand why one + two returns 1 instead of 3. I have to force context with parens. This occurs on 5.005_03 and 5.8.6, the opposite ends of the spectrum of perl that interests me.

Is this a facet of some more useful behaviour that I haven't noticed before? Could someone please enlighten me as to what is going on?

- another intruder with the mooring in the heart of the Perl

In reply to Puzzled by constant subs by grinder

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