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Missing bits in the docs.

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Georges Dupéron 2017-05-09 19:52:42 +02:00
parent a2c817c7cd
commit e572113b0c
1 changed files with 29 additions and 6 deletions
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35
scribblings/polysemy.scrbl
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@ -17,14 +17,31 @@ This module allows defining polysemic identifiers which can act as a
@tech[#:doc '(lib "scribblings/reference/reference.scrbl")]{match expander},
as a @tech[#:doc '(lib "scribblings/guide/guide.scrbl")]{macro}, as an
@tech[#:doc '(lib "scribblings/guide/guide.scrbl")]{identifier macro}, as a
@racket[set!] subform, and as a collection of
@racket[set!] subform, and as a collection of function overloads.
The following meanings are special:
@itemlist[
@item{The value for the @racket[normal-macro] meaning is used when the
identifier appears as the first element of a macro application (i.e. when it
is used as a as a @tech[#:doc '(lib "scribblings/guide/guide.scrbl")]{
macro}).}
@item{The value for the @racket[identifier-macro] meaning is used when the
identifier appears on its own as an expression (i.e. when it is used as an
@tech[#:doc '(lib "scribblings/guide/guide.scrbl")]{identifier macro}).}
@item{The value for the @racket[match-expander] meaning is used when the
identifier is used as a match template}
@item{The value for the @racket['set!-macro] meaning is used when the
identifier is appears as the second element of a @racket[set!] form.}
@item{Other "core" meanings may be added later, and third-party libraries can
define their own meanings.}]
In all the forms below, the @racket[_meaning] should be a simple identifier.
Note that is lexical context is not taken into account (i.e. it is used as a
symbol), and therefore every @racket[_meaning] should be globally unique.
Later versions may add a notion of hygiene to meanings (allowing these
meanings themselves to be renamed, to circumvent conflicts).
Note that is lexical context is not taken into account (i.e. the comparison is
based on the equality of symbols, not based on @racket[free-identifier=?]),
and therefore every @racket[_meaning] should be globally unique. Later
versions may add a notion of hygiene to meanings (allowing these meanings
themselves to be renamed, to circumvent conflicts).
@defform[#:kind "require transformer"
(poly-only-in module [maybe-rename meaning ...] ...)
@ -78,7 +95,13 @@ meanings themselves to be renamed, to circumvent conflicts).
Defines @racket[id] as a literal with the given @racket[meaning]. The
@racket[syntax-class] is automatically defined to recognise the given
@racket[meaning] of @racket[id], even if @racket[id] was renamed and its
different meanings split out and recombined into different identifiers.}
different meanings split out and recombined into different identifiers.
This can be used to define "tokens" for macros, which bear a special meaning
for some macros, but might have a different meaning for another third-party
macro. If both rely on @racketmodname[polysemy], then they can use the same
default name, without the risk of the identifiers conflicting. Furthermore, it
is possible to rename the two meanings separately.}
@defform[(define-poly-case (name [arg₀ pred?] argᵢ ...) . body)]{
Note that the syntax for this form will be changed in the future when support