If you know how (Perl-)prototypes work, it is indeed predictable, but most think the Perl-prototypes work as do prototypes in languages such as C and then they are unpleasantly surprised. This really is one of the (few) dark corners of Perl IMHO.

All parameter passing in and out of functions or subs in Perl is done by passing in or out a flat list. There is no standard mechanism to do what you describe, although I find the following template comes close:

sub my_subroutine {
    my ($required_parameter_1, $required_paramater_2, @optional_parame
+ters) = @_; 
}

[download]
Of course you would use more meaningful variable names in a real situation.

The '1/8' is the value of a hash in a scalar context. It means '1 bin out of 8 possible bins are being used'. 'Bins' are what is being used internally by a hash to store the keys and values. I have never seen any practical use for this information.

CountZero

A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James

In reply to Re^4: Perl Module by CountZero
in thread Perl Module by pparesh

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