38 lines
1.5 KiB
Racket
38 lines
1.5 KiB
Racket
#lang scribble/manual
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@require[(for-label racket/contract/base)
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scribble/example]
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@title{Using contract syntax to specify types}
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@defmodule[type-expander/contracts-to-types]
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@defform*[{(contract→type contract)
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(contract->type contract)}]{
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This is a simple type expander which translates common contracts to types.
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Note that it only supports a limited number of contract constructors. The
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following are supported: @racket[or/c], @racket[and/c] (the translation may
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produce a type too complex for Typed/Racket to understand properly, though),
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@racket[listof], @racket[list/c], @racket[*list/c], @racket[vectorof],
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@racket[vector/c], @racket[cons/c], @racket[integer?], @racket[string?],
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@racket[symbol?], @racket[exact-nonnegative-integer?],
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@racket[exact-positive-integer?], @racket['quoted-datum],
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@racket[`quasiquoted-datum-with-unquoted-types].
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Furthermore, using @racket[,_τ] anywhere outside of a quoted datum will leave
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the type @racket[_τ] unchaged, allowing the user to manually convert to types
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only the parts which cannot be converted automatically.}
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@defform*[{(:contract→type contract)
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(:contract->type contract)}]{
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Prints a representation of the contract translated as a type. It is then
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possible to copy-paste that result into the code.
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@examples[
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(require type-expander/lang
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racket/contract/base
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type-expander/contracts-to-types)
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(:contract→type (list/c 1 2 "str" (or/c integer? string?)))]
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}
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