44 lines
2.0 KiB
Racket
44 lines
2.0 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[number?], @racket[integer?],
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@racket[string?], @racket[symbol?], @racket[char?], @racket[boolean?],
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@racket[bytes?], @racket[void?], @racket[null?], @racket[empty?],
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@racket[list?], @racket[exact-nonnegative-integer?],
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@racket[exact-positive-integer?], @racket[syntax/c], @racket[parameter/c],
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@racket[promise/c], @racket[suggest/c], @racket[flat-rec-contract], some uses
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of @racket[->] and @racket[->*], @racket['quoted-datum],
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@racket[`quasiquoted-datum-with-unquoted-types]. Literal data (numbers,
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strings, characters, booleans, byte strings, regular expressions and byte
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regular expressions) are also interpreted as singleton 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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