OK, I'm confused. map wants a list, right? So here you're treating the hash as a list, and setting the undefined values to '' as you find them?

I think that this method would make more sense to me if it went something like 

map { $_ = '' unless defined } values %$ref2;

[download]
I guess I'm just wondering why referring to hashes in a list context is a good idea.

Update: merlyn rightly points out this is a void usage of map. Perusing the docs for map led me to some insight. We want to test for values that are undefined and change them -- sounds like a job for grep: 

for (grep {not defined} values %$ref2) {$_ = q()};

[download]
fits the bill -- it actually acts on the returned values from grep, so no more void contexts, and actually reads like the task desired.

In reply to Re: Re: setting values in anonymous hash by snax
in thread setting values in anonymous hash by agoth

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