Ah, that changes things a fair bit. I was merely going by the behaviour you had originally - $4 eq 'play' doesn't return 'true' and 'false' but '1' and undef. One alternative is to use a function that converts, such as: 

sub bool2str
{
  shift ? 'true' : 'false'
}

[download]
Then you could use bool2str($control{play}) to get the strings you want.

In reply to Re^3: setting up boolean parameters from keywords by Tanktalus
in thread setting up boolean parameters from keywords by rand0mmm

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