Should struct have an #:extra-id-name ?

[Jens Axel Søgaard]

Consider this snippet from scribble/html/xml

(provide make-element)

(struct element (tag attrs body [cache #:auto #:mutable])

  #:constructor-name make-element

  #:transparent #:omit-define-syntaxes #:auto-value #f

  #:property prop:procedure

  (lambda (e)

    (unless (element-cache e) (set-element-cache! e (element->output e)))

    (element-cache e)))

(provide element)

(define (element tag . args)

  (define-values [attrs body] (attributes+body args))

  (make-element tag attrs body))

I would like to provide the structure definition, but simply adding (provide (struct-out element)) does not work, since  element  is not bound to the structure id.

An #:extra-id-name option for struct could solve this.

Is there another way to provide the struct element without renaming the element function?

/Jens Axel

--

--
Jens Axel Søgaard

[Jens Axel Søgaard]

Ping.

[Matthew Flatt]

I can't think of a good alternative, and a way to provide a name for
the static info sounds fine to me.

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[Jens Axel Søgaard]

For the archives:

    https://github.com/racket/racket/pull/1309

I have added #:extra-id-name and tried to mimic the coding style.

In    (struct foo (bar) #:extra-id-name baz)

the struct information in the compile time variable foo

and baz will be shared.

In    (struct foo (bar) #:extra-id-name baz

                                 #:omit-define-syntaxes)

the information will only be stored in baz.

Example:

#lang racket

(provide (struct-out baz))

(struct foo (bar)

  #:transparent

  #:extra-id-name baz

  #:omit-define-syntaxes

  #:omit-define-values

  #:constructor-name Foo)

(define (foo x)

  (Foo 42))

(foo 42)

produces a struct  value containing 42.

Does the approach look reasonable?

/Jens Axel