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Re: Generics for a multiplevalue hashmap

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Subject	Re: Generics for a multiplevalue hashmap
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On 11-07-18 06:31 PM, Alexis Berry wrote:
> Hello,
> 
> I want to create a HashMap which has a list for each key. Therefore I can store more than one value for each key. (I know this breaks the true use of a hashmap but I want a datastruture that takes one key and hold multiple value)
>
Why does it break the "true use" of a hashmap? The use of a map or
dictionary or associative array - whatever you choose to call it - is to
relate a collection of keys and values such that each key is associated
with a value. That value may be anything, including a list or set of values.

As it happens a map which has lists or sets as values is a typical
implementation of a so-called multimap. Good multimap interfaces make
the implementation easier to use but don't hide it much. See the
Wikipedia entry on multimap for some references to implementations.

I won't address the rest of the post because others will already be all
over it. :-)

AHS

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Thread

Generics for a multiplevalue hashmap Alexis Berry <iamrichardjones@gmail.com> - 2011-07-18 14:31 -0700
  Re: Generics for a multiplevalue hashmap markspace <-@.> - 2011-07-18 14:40 -0700
  Re: Generics for a multiplevalue hashmap Arved Sandstrom <asandstrom3minus1@eastlink.ca> - 2011-07-18 21:00 -0300
  Re: Generics for a multiplevalue hashmap Arne Vajhøj <arne@vajhoej.dk> - 2011-07-18 23:01 -0400
  Re: Generics for a multiplevalue hashmap Roedy Green <see_website@mindprod.com.invalid> - 2011-07-19 03:59 -0700
  Re: Generics for a multiplevalue hashmap Esmond Pitt <esmond.pitt@bigpond.com> - 2011-07-19 22:24 +1000
    Re: Generics for a multiplevalue hashmap markspace <-@.> - 2011-07-19 08:31 -0700

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