sub foo { print 'bar' } 
$var = 'foo'; 
main->$var;
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However, this calls "foo" as a class method, so the sub gets the classname as the first argument. If you dont want that, use a dispatch table.

%subs = (
  'foo' => \&foo,
  'bar' => \&bar,
  # etc
);
print $subs{$var}->($arg1, $arg2);
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