This site is a static rendering of the Trac instance that was used by R7RS-WG1 for its work on R7RS-small (PDF), which was ratified in 2013. For more information, see Home.

Source for wiki SyntaxDefinitions version 3

author

cowan

comment

ipnr

127.11.51.1

name

SyntaxDefinitions

readonly

text

These tests show the type of syntax definitions the Schemes in the suite understand.  The following Schemes do not support syntax extension of any (known) kind, and are excluded below:  NexJ, JScheme, KSi, Shoe, !TinyScheme, BDC, XLisp, Schemik, UMB, Llava, !FemtoLisp, Oaklisp, Inlab

== Define-macro ==

`Define-macro` is a low-level bare macro definition, analogous to Common Lisp `defmacro`.  I tested `(define-macro x (lambda (y) y))` followed by `(x (+ 3 4))`, expecting it to return 7 on Schemes that support `define-macro` and an error otherwise.  `Define-macro` is not part of any Scheme standard.

Supported: Gambit, Bigloo, Guile, Kawa, SISC, Ypsilon, !SigScheme, S7[*], Scheme 9, STklos, RScheme, Rep, Elk, Dfsch[*], Picrin

Not supported: Racket, Gauche, MIT, Chicken, Scheme48/scsh, SCM, Chez, Vicare, Larceny, Mosh, !IronScheme, SXM, Sagittarius, Foment, Owl Lisp, Chibi, Sizzle[*]

[*] S7 and Dfsch accept the `define`-style syntax `(define-macro (x y) y)` only.  The Sizzle documentation claims to do the same, but it didn't work for me.

== Define-syntax ==

`Define-syntax` is a wrapper for any of the following syntax transformations.  Other such wrappers are `let-syntax`, `let*-syntax`, and `letrec-syntax`, which define local macros.  The following additional Schemes do not support `define-syntax` and are excluded below: !SigScheme, S7, Rep, Elk, Sizzle, Dfsch.  RScheme accepts only a non-standard form of `define-syntax` and is also excluded below.


=== Syntax-rules ===

`Syntax-rules` is a syntax transformer used with `define-syntax` and its relatives.  It was described but not standardized in R4RS; with minor extensions, it is part of the R5RS, R6RS, and R7RS-small standards.  I tested `(define-syntax x (syntax-rules () ((x y) y)))`, which is essentially equivalent to the `define-macro` macro used above, but with hygiene.

Supported: Racket, Gauche, MIT, Gambit (with the `-:s` switch), Chicken, Bigloo, Scheme48/scsh, Guile, Kawa, SISC, SCM (with the `-r5 -m` switches), Chez, Vicare, Larceny, Ypsilon, Mosh, !IronScheme, STklos, Scheme 9, SXM, Sagittarius, Foment, Picrin, Owl Lisp, Chibi

Not supported: (none)

=== Syntax-case ===

`Syntax-case` is a hybrid low/high-level macro system that is standardized in R6RS.  The test used here is `(define-syntax x (lambda (x) (syntax-case x () ((x y) (syntax y)))))`, which is exactly equivalent to the `syntax-rules` macro used above.

Supported: Racket, Gambit, Guile, Kawa, SISC, Chez, Vicare, Larceny, Ypsilon, Mosh, !IronScheme, SXM, Sagittarius

Not supported:  Gauche, MIT, Chicken, Bigloo, Scheme48/scsh, SCM, STklos, Scheme 9, Foment, Picrin, Owl Lisp, Chibi

=== Syntactic closures ===

Syntactic closures is a low-level macro system supported by MIT and Chibi only.

=== Explicit renaming ===

Explicit renaming is a low-level macro system supported by MIT, Chicken, Chibi [others?].

=== Implicit renaming ===

Implicit renaming is a low-level macro system supported by Chicken only.

time

2015-05-31 07:21:07