this only lasts locally in this sub

# Creates a hash %t that has the same contents as %toys
my %t = %{$_[0]};

# Modifies %t (which is unrelated to %toys)
$t{'leggo'} = "yes";

[download]

[$_[0]{'leggo'} = "yes";] is darned ugly!

Since you're not changing the reference itself (only that to which it refers), you can copy the reference into a more suitably named variable. 

my ($toys) = @_;
$toys->{'leggo'} = 1;

[download]

Note that 1 and 0 (or undef) are usually used for boolean. It's not that using "yes" is problematic, it's that "no" isn't false. Formatting outputs (e.g. converting to "yes" and "no") should be done on output.

In reply to Re: passing of variables by ikegami
in thread passing of variables by itsscott

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