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Source for wiki SyntaxDefinitions version 7

author

cowan

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ipnr

127.11.51.1

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SyntaxDefinitions

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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, Picrin, Chibi.

=== Explicit renaming ===

Explicit renaming is a low-level macro system supported by MIT, Chicken, Sagittarius, Picrin, Chibi, Larceny (with different syntax).

=== Implicit renaming ===

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

time

2016-05-21 05:04:31