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gfortran compiling problem,calling too many arguments
01-16-2011
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Signature(3pm) User Contributed Perl Documentation Signature(3pm) NAME
perl5i::Signature - Representing what parameters a subroutine accepts SYNOPSIS
func hello( $greeting, $place ) { say "$greeting, $place" } my $code = &hello; my $signature = $code->signature; say $signature->num_positional_params; # 2 say $signature->is_method; # false DESCRIPTION
A Signature is a representation of what parameters a subroutine accepts. Each subroutine defined with "func" or "method" will have a signature associated with it. You can get at it by calling the "signature" method on the code reference. See "Signature Introspection" in perl5i for more details. Subroutines declared with Perl's built in "sub" will have no signature. METHODS
params my $params = $sig->params; An array ref of the parameters a subroutine takes in the order it takes them. Currently they are just strings. In the future they will be string overloaded objects. positional_params my $params = $sig->positional_params; Like "$sig->params" but it is just the positional parameters. In the future there will be named parameters. num_positional_params my $num_positional_params = $sig->num_positional_params; The number of named parameters the subroutine takes. In the future there will be named parameters. For the purposes of determining how many arguments a function takes, it is most useful to look just at the positional ones. This is mostly an optimization for "$sig->positional_params->size". as_string my $params = $sig->as_string; The original signature string. invocant my $invocant = $sig->invocant; The invocant is the object or class a method is called on. "invocant" will return the parameter which contains this, by default it is $self on a method, and nothing a regular subroutine. is_method my $is_method = $sig->is_method; Returns if the subroutine was declared as a method. OVERLOADING
Signature objects are string overloaded to return "as_string". They are also always true to avoid objects taking no parameters from being confused with subroutines with no signatures. perl v5.14.2 2012-06-14 Signature(3pm)