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Introduction

Structures are the built in records in PLT. SRFI9 provides portable records.

A stucture type is a record datatype with a number of fields. A structure is an instance of a given structure type. Structures are first class values that contain a value for each field of the the structure type.

;; Small usage example

> (define-struct user (name password))
> (define guest (make-user "Anonymous" "1234")
> (user? guest)
#t
> (user-name guest)
"Anonymous"
> (set-user-name! guest "Guest")
> (user-name guest)
"Guest"

See Structures - Chapter 4 in the MzScheme documentation for a thorough explanation of the use of structures.

-- JensAxelSoegaard - 04 Jun 2004