Because when delete=0, then param('delete') returns 0. When evaluated in boolean context (which is what if does), 0 is false and all other values are true.

I think what you want is if(defined param('delete')) { . . . }. defined() returns true if the value given is actually defined, but doesn't care what it was defined as.

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I wanted to explore how Perl's closures can be manipulated, and ended up creating an object system by accident.
-- Schemer

Note: All code is untested, unless otherwise stated