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Introduction

PLT Scheme provides basic, but useful and fast ways of manipulating hashes. A hash table is used to store a collection of data values associated with keys.

To create a hash table use make-hash-table, which receives two optional arguments to create tables with weakly-held keys, and to use different comparison procedures. We will discuss this variations later, so for the time being something like:

(make-hash-table)

creates a new hash table. By default this table will compare keys using eq?. If you want to use keys that need a stronger equality test (i.e., strings), you can provide make-hash-table with the argument equal:

(make-hash-table 'equal)

In the following recipes we will discuss ways to manipulate our newly created hash table.

-- KarlaRamirez - 19 May 2004

-- GordonWeakliem - 17 Sep 2004