Others have already pointed to modules, here is a simple, if eventually laborious, non-prototype solution:

As already mentioned, evaluating @_ in scalar context will check the number of arguments, but you must remember that if a method is called on an object, @_ automatically receives as its first "argument" the object reference, which is why most methods start with the line my $self = shift which retrieves/removes the reference from the arg list.

As for type validation, it depends what you mean. If you mean scalar/array/hash, then you can employ the ref() operator on each argument and compare the return value to what you expect, as in unless ref($arg1) eq 'HASH'... or whatever. For evaluating the type for object arguments, use the isa() operator, as in unless $self->isa(Bogus::Object).... isa() is superior to ref() in this context because it works with inheritance, returning true if the object IS-A instance of Bogus::Object or any of its children. Checking "types" any more pedantically (such as integer, string etc.) will involve using regexes (ugh) and if that's the case just use Java or something that has such support built into the language, or wait for Perl6.


In reply to Re: validating function input by Anonymous Monk
in thread validating function input by bobdeath

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