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One thing is that you can pass a reference to a hash instead and then simply replace
my ($host)=@_; $host="foo";
with
my $hash=shift; $hash->{host}="foo";
Another issue I've found when passing user generated hashes, or hashrefs, as parameters is that its easy to make errors. Just misspell a key name and you've got an error, sometimes one that is hard to track down. So ive found its worth the time to add code to trap incorrect keys. This is nice because similar to drewbies and IraTarballs code it provides defaults as well. Which I find usefull in a constructor, one place where you tend to get named parameter calling conventions.
package Foo; use strict; use Carp; use Data::Dumper; my %defaults=( a => "sn",b=>"afu" ); sub test{shift; print "test:",shift,"\n"} sub test2{&test}; sub new { my $class = shift; my $attrs = shift; my %params = @_; my $self=bless {%defaults},$class; for my $param (keys %params) { croak "Unknown param $param" unless exists($self->{$param}); $self->{$param}=$params{$param}; } for my $attr (keys %$attrs) { croak "Unknown attribute" unless $self->can($attr); $self->$attr($attrs->{$attr}); } return $self; } my $t=Foo->new( { test=>"Hello", test2=>"There", },a=>1,b=>2); my $tt=Foo->new(); print Dumper $t,$tt;
It might be a bit long but the point was to show that with perl you have a lot of flexibility in how you can call a subroutine but that it leaves all the errorchecking to you.

Yves
--
You are not ready to use symrefs unless you already know why they are bad. -- tadmc (CLPM)


In reply to Re: passing subroutine arguments directly into a hash by demerphq
in thread passing subroutine arguments directly into a hash by c

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