First, I always put an explicit return statement in a subroutine rather than relying upon "return value of last statement" except in sort{} blocks where no return statement is the norm.

When you call a sub() in an expression, the paren's are normally required. There are built in functions and ways to make a user defined function work like a built in function with prototypes.

The simple answer here is to call sub1() and sub2() with no arguments, use sub1(), etc. Don't use a bare word sub name for a normal user defined sub/function. 

#!usr/bin/perl
use strict;
use warnings;

sub sub1{return 2}
sub sub2{return 2}

my ($a, $b) = (sub1, sub2);
my ($s, $t) = ((2*sub1()+sub2()), (2*$a+$b));


say STDERR "$a==", sub1;
say STDERR "$b==", sub2;
say STDERR "$s==$t";

__END__
2==2
2==2
6==6

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In reply to Re: Constant code by Marshall
in thread Constant code by philiprbrenan

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