HashRetrieve - Cookbook - s c h e m a t i c s : c o o k b o o k

Retrieving an Element from a Hash

Problem

You need to retrieve an item from a Hash.

Solution

Just use hash-table-get.

(define (hash-table-get-example)
  (let ((example-hash-table (make-hash-table 'equal)))
    (hash-table-put! example-hash-table "key1" "value1")
    (hash-table-put! example-hash-table "key2" "value2")
    (hash-table-put! example-hash-table "key3" "value3")
    (hash-table-get example-hash-table "key2")))

> (hash-table-get-example)
"value2"

Discussion

Note the 'equal argument to make-hash-table. Without it, we would not be able to use strings as our keys.

Contributors

-- LukeRenn - 21 Feb 2006

CookbookForm
TopicType:	Recipe
ParentTopic:	HashRecipes
TopicOrder:	020

Current Rev: r1.2 - 21 Feb 2006 - 21:20 GMT - LukeRenn, Revision History:Diffs | r1.2 | > | r1.1

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s c h e m a t i c s : c o o k b o o k

Retrieving an Element from a Hash

Problem

Solution

Discussion

Comments about this recipe

Contributors