These interpolate:

These do not:

TL;DR: if you want interpolation, don't use single quotes!

OK, I see what you're asking. You want delayed evaluation - I'll update with a solution to that momentarily!

Update: OK, how about this...

use v5.10;
use strict;
use warnings;

sub delayed (&) {
    package delayed;
    use overload q[""] => sub { $_[0]->() }, fallback => 1;
    bless shift;
}

my $string = delayed {"Look $::person, no $::thing!"};

$::person = "Ma";
$::thing  = "stringy eval";

say $string;

[download]

Update II (about a week later): I've released String::Interpolate::Delayed using some of the ideas explored in this thread.

package Cow { use Moo; has name => (is => 'lazy', default => sub { 'Mooington' }) } say Cow->new->name

In reply to Re: Interpolation: when it occurs? another beginner question.. by tobyink
in thread Interpolation: when it occurs? another beginner question.. by Discipulus

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