Can we strict the subroutine in perl to receive number of arguments ?
Runtime? Compile time? Is @a considered to be one argument, or as many arguments as @a has elements?

Runtime is easy: 

sub foo {
    unless (@_ <= 4) {
        die "foo allows at most 4 arguments";
    }
    ...
}

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Compile time, you can do: 
sub foo (;$$$$) {
    ...
}

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The disadvantage of the latter is that it evaluates all the arguments to the sub in scalar context, and hence there's no flattening of lists. That is, 
@bar = qw[red blue green yellow brown pink];
foo @bar;

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is not an error - it calls foo with a single argument, 6; the number of elements in @bar.

In reply to Re: Limit number of Sub routine argument list by JavaFan
in thread Limit number of Sub routine argument list by ganeshwari

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