I pulled a late-nighter and with the morning comes brain block. Please save an old man a few brain cells... How do I get the following code to DWIM? 
#!/usr/bin/perl -w
use strict;

my $str  = 'abcadefaghi';
my $pat  = '(a.)';
my $repl = '$1 ';

#$str =~ s/$pat/$1 /g;   # Working non-dynamic demo
$str =~ s/$pat/$repl/g;

print "$str\n";          # prints: '$1 c$1 ef$1 hi'

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Obviously the '$1' is being taken as a literal when it is included in the variable replacement string. And the regex lobe in my brain has gone numb.

$repl could be any legal regex replacement string. (?{...}) constructions will be filtered out before the regex is invoked even though these come from a trusted source.)

(Coffee... must have coffee...)

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"Perl is a mess and that's good because the
problem space is also a mess." - Larry Wall

In reply to $1 in variable regex replacement string by dvergin

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