It can be done with eval:

#! /usr/bin/perl -w

my $a = 'sub { $name = shift; return substr($name, 0, 1); }';
my $b = eval $a ;
print &$b("wiredrat");
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However, i don't know if it can be done without eval-ing it into $b. Hope this help you.

2005-02-16 Janitored by Arunbear - added code tags, as per Monastery guidelines