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How do I dynamically create a hash table?

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Contributed by Anonymous Monk on Oct 27, 2000 at 02:39 UTC
Q&A  > hashes


Answer: How do I dynamically create a hash table?
contributed by tedv

use strict; my %hash = (); foreach $value (@some_list) { my $key = make_some_key($value); $hash{$key} = $value; }

In other words, just assign a new key/value pair using $hash{$key} = $value. It's the logical compliment of how you'd access a hash value: $value = $hash{$key}

-Ted
Answer: How do I dynamically create a hash table?
contributed by Anonymous Monk

In only 1 line!

%new_hash = (split(/;/,$variable_with_keys_and_values));
For example:
%new_hash = (split(/;/,'apple;good;banana;good;citrus;good;no doughnut +;bad cop')); print $new_hash{'no doughnut'};
Outputs the value associated with the key 'no doughnut'
Answer: How do I dynamically create a hash table?
contributed by kharris

I just got done with this sort of thing. It looks like this.

my ($url, @rest, $url_rec, @url_keys); ($url, @rest)=split /\|/,$_; if($#rest == 3) # We're re-building. { @url_keys= qw{url_last_checked_return_code url_cat_id url_descriptio +n url_last_checked}; } if($#rest == 1) # We're adding. { @url_keys = qw{url_cat_id url_description}; } foreach my $key (@url_keys) { $url_rec->{$key} = pop @rest; }

I know that someone above adept-level could have done this more elegantly efficiently, but it works...so far. ;-)

kevin

Answer: How do I dynamically create a hash table?
contributed by Anonymous Monk

We have tried out this way:

@list_of_elements = split /;/,$variable_with_keys_and_values);
%new_hash = (@list_of_elements);

We think this is more simple (just two lines!)

- Franco e Giuseppe.

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