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3.1 Porting Untyped Modules to Typed Racket
5.92

3 Libraries Provided With Typed Racket

The typed/racket language corresponds to the racket language—that is, any identifier provided by racket, such as modulo is available by default in typed/racket.

#lang typed/racket
(modulo 12 2)

The typed/racket/base language corresponds to the racket/base language.

Some libraries have counterparts in the typed collection, which provide the same exports as the untyped versions. Such libraries include srfi/14, net/url, and many others.

#lang typed/racket
(require typed/srfi/14)
(char-set= (string->char-set "hello")
           (string->char-set "olleh"))

Other libraries can be used with Typed Racket via require/typed.

#lang typed/racket
(require/typed version/check
               [check-version (-> (U Symbol (Listof Any)))])
(check-version)

The following libraries are included with Typed Racket in the typed collection:

 (require typed/file) package: typed-racket-more
 (require typed/net/base64) package: typed-racket-more
 (require typed/net/cgi) package: typed-racket-more
 (require typed/net/cookie) package: typed-racket-more
 (require typed/net/dns) package: typed-racket-more
 (require typed/net/ftp) package: typed-racket-more
 (require typed/net/gifwrite) package: typed-racket-more
 (require typed/net/head) package: typed-racket-more
 (require typed/net/imap) package: typed-racket-more
 (require typed/net/mime) package: typed-racket-more
 (require typed/net/nntp) package: typed-racket-more
 (require typed/net/pop3) package: typed-racket-more
 (require typed/net/qp) package: typed-racket-more
 (require typed/net/sendmail) package: typed-racket-more
 (require typed/net/sendurl) package: typed-racket-more
 (require typed/net/smtp) package: typed-racket-more
 (require typed/net/uri-codec)
  package: typed-racket-more
 (require typed/net/url) package: typed-racket-more
 (require typed/rackunit) package: typed-racket-more
 (require typed/srfi/14) package: typed-racket-more

Other libraries included in the main distribution that are either written in Typed Racket or have adapter modules that are typed:

 (require math) package: math-lib
 (require plot/typed) package: plot-gui-lib

3.1 Porting Untyped Modules to Typed Racket

To adapt a Racket library not included with Typed Racket, the following steps are required:

For example, the following module adapts the untyped racket/bool library:

#lang typed/racket
(require/typed racket/bool
               [true Boolean]
               [false Boolean]
               [symbol=? (Symbol Symbol -> Boolean)]
               [boolean=? (Boolean Boolean -> Boolean)]
               [false? (Any -> Boolean)])
(provide true false symbol=? boolean=? false?)

More substantial examples are available in the typed collection.