The problem is that your ?: line is parsed by Perl as: 
($base_string =~ /^#/ ? ($foo = $') : $bar)
  = $base_string;

[download]
Add parens to your expression to get the operations to occur in the right manner: 
$base_string =~ /^#/ ?
  ($foo = $') :
  ($bar = $base_string);

[download]

In reply to Re: Why won't $' work in a trinary operation? by japhy
in thread Why won't $' work in a trinary operation? by satchboost

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