From c7a50f632293cf88f241d45d1fd52fa2f58ce772 Mon Sep 17 00:00:00 2001 From: Arne Babenhauserheide Date: Fri, 3 Feb 2023 22:20:04 +0100 Subject: [PATCH] Add language/wisp, wisp tests, and srfi-119 documentation * doc/ref/srfi-modules.texi (srfi-119): add node * module/language/wisp.scm: New file. * module/language/wisp/spec.scm: New file. * test-suite/tests/srfi-119.test: New file. --- doc/ref/srfi-modules.texi | 30 ++ module/language/wisp.scm | 761 +++++++++++++++++++++++++++++++++ module/language/wisp/spec.scm | 85 ++++ test-suite/tests/srfi-119.test | 81 ++++ 4 files changed, 957 insertions(+) create mode 100644 module/language/wisp.scm create mode 100644 module/language/wisp/spec.scm create mode 100644 test-suite/tests/srfi-119.test diff --git a/doc/ref/srfi-modules.texi b/doc/ref/srfi-modules.texi index 0ef136215..759e293ec 100644 --- a/doc/ref/srfi-modules.texi +++ b/doc/ref/srfi-modules.texi @@ -64,6 +64,7 @@ get the relevant SRFI documents from the SRFI home page * SRFI-98:: Accessing environment variables. * SRFI-105:: Curly-infix expressions. * SRFI-111:: Boxes. +* SRFI-119:: Wisp: simpler indentation-sensitive scheme. * SRFI-171:: Transducers @end menu @@ -5662,6 +5663,34 @@ Return the current contents of @var{box}. Set the contents of @var{box} to @var{value}. @end deffn +@node SRFI-119 +@subsection SRFI-119 Wisp: simpler indentation-sensitive scheme. +@cindex SRFI-119 +@cindex wisp + +The languages shipped in Guile include SRFI-119 (wisp), an encoding of +Scheme that allows replacing parentheses with equivalent indentation and +inline colons. See +@uref{http://srfi.schemers.org/srfi-119/srfi-119.html, the specification +of SRFI-119}. Some examples: + +@example +display "Hello World!" @result{} (display "Hello World!") +@end example + +@example +define : factorial n @result{} (define (factorial n) + if : zero? n @result{} (if (zero? n) + . 1 @result{} 1 + * n : factorial @{n - 1@} @result{} (* n (factorial @{n - 1@})))) +@end example + +To execute a file with wisp code, select the language and filename +extension @code{.w} vie @code{guile --language=wisp -x .w}. + +In files using Wisp, @xref{SRFI-105} (Curly Infix) is always activated. + + @node SRFI-171 @subsection Transducers @cindex SRFI-171 @@ -5705,6 +5734,7 @@ left-to-right, due to how transducers are initiated. * SRFI-171 Helpers:: Utilities for writing your own transducers @end menu + @node SRFI-171 General Discussion @subsubsection SRFI-171 General Discussion @cindex transducers discussion diff --git a/module/language/wisp.scm b/module/language/wisp.scm new file mode 100644 index 000000000..7a12e126a --- /dev/null +++ b/module/language/wisp.scm @@ -0,0 +1,761 @@ +;;; Wisp + +;; Copyright (C) 2013, 2017, 2018, 2020 Free Software Foundation, Inc. +;; Copyright (C) 2014--2023 Arne Babenhauserheide. +;; Copyright (C) 2023 Maxime Devos + +;;;; This library is free software; you can redistribute it and/or +;;;; modify it under the terms of the GNU Lesser General Public +;;;; License as published by the Free Software Foundation; either +;;;; version 3 of the License, or (at your option) any later version. +;;;; +;;;; This library is distributed in the hope that it will be useful, +;;;; but WITHOUT ANY WARRANTY; without even the implied warranty of +;;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +;;;; Lesser General Public License for more details. +;;;; +;;;; You should have received a copy of the GNU Lesser General Public +;;;; License along with this library; if not, write to the Free Software +;;;; Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + +;;; Commentary: + +;; Scheme-only implementation of a wisp-preprocessor which output a +;; scheme code tree to feed to a scheme interpreter instead of a +;; preprocessed file. + +;; Limitations: +;; - in some cases the source line information is missing in backtraces. +;; check for set-source-property! + +;;; Code: + +(define-module (language wisp) + #:export (wisp-scheme-read-chunk wisp-scheme-read-all + wisp-scheme-read-file-chunk wisp-scheme-read-file + wisp-scheme-read-string)) + +; use curly-infix by default +(read-enable 'curly-infix) + +(use-modules + (srfi srfi-1) + (srfi srfi-11); for let-values + (ice-9 rw); for write-string/partial + (ice-9 match)) + + +;; Helper functions for the indent-and-symbols data structure: '((indent token token ...) ...) +(define (line-indent line) + (car line)) + +(define (line-real-indent line) + "Get the indentation without the comment-marker for unindented lines (-1 is treated as 0)." + (let (( indent (line-indent line))) + (if (= -1 indent) + 0 + indent))) + +(define (line-code line) + (let ((code (cdr line))) + ; propagate source properties + (when (not (null? code)) + (set-source-properties! code (source-properties line))) + code)) + +; literal values I need +(define readcolon + (string->symbol ":")) + +(define wisp-uuid "e749c73d-c826-47e2-a798-c16c13cb89dd") +; define an intermediate dot replacement with UUID to avoid clashes. +(define repr-dot ; . + (string->symbol (string-append "REPR-DOT-" wisp-uuid))) + +; allow using reader additions as the first element on a line to prefix the list +(define repr-quote ; ' + (string->symbol (string-append "REPR-QUOTE-" wisp-uuid))) +(define repr-unquote ; , + (string->symbol (string-append "REPR-UNQUOTE-" wisp-uuid))) +(define repr-quasiquote ; ` + (string->symbol (string-append "REPR-QUASIQUOTE-" wisp-uuid))) +(define repr-unquote-splicing ; ,@ + (string->symbol (string-append "REPR-UNQUOTESPLICING-" wisp-uuid))) + +(define repr-syntax ; #' + (string->symbol (string-append "REPR-SYNTAX-" wisp-uuid))) +(define repr-unsyntax ; #, + (string->symbol (string-append "REPR-UNSYNTAX-" wisp-uuid))) +(define repr-quasisyntax ; #` + (string->symbol (string-append "REPR-QUASISYNTAX-" wisp-uuid))) +(define repr-unsyntax-splicing ; #,@ + (string->symbol (string-append "REPR-UNSYNTAXSPLICING-" wisp-uuid))) + +; TODO: wrap the reader to return the repr of the syntax reader +; additions + +(define (match-charlist-to-repr charlist) + (let + ((chlist (reverse charlist))) + (cond + ((equal? chlist (list #\.)) + repr-dot) + ((equal? chlist (list #\')) + repr-quote) + ((equal? chlist (list #\,)) + repr-unquote) + ((equal? chlist (list #\`)) + repr-quasiquote) + ((equal? chlist (list #\, #\@)) + repr-unquote-splicing) + ((equal? chlist (list #\# #\')) + repr-syntax) + ((equal? chlist (list #\# #\,)) + repr-unsyntax) + ((equal? chlist (list #\# #\`)) + repr-quasisyntax) + ((equal? chlist (list #\# #\, #\@)) + repr-unsyntax-splicing) + (else + #f)))) + +(define (wisp-read port) + "wrap read to catch list prefixes." + (let ((prefix-maxlen 4)) + (let longpeek + ((peeked '()) + (repr-symbol #f)) + (cond + ((or (< prefix-maxlen (length peeked)) (eof-object? (peek-char port)) (equal? #\space (peek-char port)) (equal? #\newline (peek-char port))) + (if repr-symbol ; found a special symbol, return it. + repr-symbol + (let unpeek + ((remaining peeked)) + (cond + ((equal? '() remaining) + (read port)); let read to the work + (else + (unread-char (car remaining) port) + (unpeek (cdr remaining))))))) + (else + (let* + ((next-char (read-char port)) + (peeked (cons next-char peeked))) + (longpeek + peeked + (match-charlist-to-repr peeked)))))))) + + + +(define (line-continues? line) + (equal? repr-dot (car (line-code line)))) + +(define (line-only-colon? line) + (and + (equal? ":" (car (line-code line))) + (null? (cdr (line-code line))))) + +(define (line-empty-code? line) + (null? (line-code line))) + +(define (line-empty? line) + (and + ; if indent is -1, we stripped a comment, so the line was not really empty. + (= 0 (line-indent line)) + (line-empty-code? line))) + +(define (line-strip-continuation line) + (if (line-continues? line) + (append + (list + (line-indent line)) + (cdr (line-code line))) + line)) + +(define (line-strip-indentation-marker line) + "Strip the indentation markers from the beginning of the line" + (cdr line)) + +(define (indent-level-reduction indentation-levels level select-fun) + "Reduce the INDENTATION-LEVELS to the given LEVEL and return the value selected by SELECT-FUN" + (let loop + ((newlevels indentation-levels) + (diff 0)) + (cond + ((= level (car newlevels)) + (select-fun (list diff indentation-levels))) + ((< level (car newlevels)) + (loop + (cdr newlevels) + (1+ diff))) + (else + (throw 'wisp-syntax-error "Level ~A not found in the indentation-levels ~A."))))) + +(define (indent-level-difference indentation-levels level) + "Find how many indentation levels need to be popped off to find the given level." + (indent-level-reduction indentation-levels level + (lambda (x); get the count + (car x)))) + +(define (indent-reduce-to-level indentation-levels level) + "Find how many indentation levels need to be popped off to find the given level." + (indent-level-reduction indentation-levels level + (lambda (x); get the levels + (car (cdr x))))) + +(define (chunk-ends-with-period currentsymbols next-char) + "Check whether indent-and-symbols ends with a period, indicating the end of a chunk." + (and (not (null? currentsymbols)) + (equal? #\newline next-char) + (equal? repr-dot + (list-ref currentsymbols (- (length currentsymbols) 1))))) + +(define (wisp-scheme-read-chunk-lines port) + (let loop + ((indent-and-symbols (list)); '((5 "(foobar)" "\"yobble\"")(3 "#t")) + (inindent #t) + (inunderscoreindent (equal? #\_ (peek-char port))) + (incomment #f) + (currentindent 0) + (currentsymbols '()) + (emptylines 0)) + (cond + ((>= emptylines 2); the chunk end has to be checked + ; before we look for new chars in the + ; port to make execution in the REPL + ; after two empty lines work + ; (otherwise it shows one more line). + indent-and-symbols) + (else + (let ((next-char (peek-char port))) + (cond + ((eof-object? next-char) + (append indent-and-symbols (list (append (list currentindent) currentsymbols)))) + ((and inindent (zero? currentindent) (not incomment) (not (null? indent-and-symbols)) (not inunderscoreindent) (not (or (equal? #\space next-char) (equal? #\newline next-char) (equal? (string-ref ";" 0) next-char)))) + (append indent-and-symbols)); top-level form ends chunk + ((chunk-ends-with-period currentsymbols next-char) + ; the line ends with a period. This is forbidden in + ; SRFI-119. Use it to end the line in the REPL without + ; showing continuation dots (...). + (append indent-and-symbols (list (append (list currentindent) (drop-right currentsymbols 1))))) + ((and inindent (equal? #\space next-char)) + (read-char port); remove char + (loop + indent-and-symbols + #t ; inindent + #f ; inunderscoreindent + #f ; incomment + (1+ currentindent) + currentsymbols + emptylines)) + ((and inunderscoreindent (equal? #\_ next-char)) + (read-char port); remove char + (loop + indent-and-symbols + #t ; inindent + #t ; inunderscoreindent + #f ; incomment + (1+ currentindent) + currentsymbols + emptylines)) + ; any char but whitespace *after* underscoreindent is + ; an error. This is stricter than the current wisp + ; syntax definition. TODO: Fix the definition. Better + ; start too strict. FIXME: breaks on lines with only + ; underscores which should be empty lines. + ((and inunderscoreindent (and (not (equal? #\space next-char)) (not (equal? #\newline next-char)))) + (throw 'wisp-syntax-error "initial underscores without following whitespace at beginning of the line after" (last indent-and-symbols))) + ((equal? #\newline next-char) + (read-char port); remove the newline + ; The following two lines would break the REPL by requiring one char too many. + ; if : and (equal? #\newline next-char) : equal? #\return : peek-char port + ; read-char port ; remove a full \n\r. Damn special cases... + (let* ; distinguish pure whitespace lines and lines + ; with comment by giving the former zero + ; indent. Lines with a comment at zero indent + ; get indent -1 for the same reason - meaning + ; not actually empty. + ((indent + (cond + (incomment + (if (= 0 currentindent); specialcase + -1 + currentindent)) + ((not (null? currentsymbols)); pure whitespace + currentindent) + (else + 0))) + (parsedline (append (list indent) currentsymbols)) + (emptylines + (if (not (line-empty? parsedline)) + 0 + (1+ emptylines)))) + (when (not (= 0 (length parsedline))) + ; set the source properties to parsedline so we can try to add them later. + (set-source-property! parsedline 'filename (port-filename port)) + (set-source-property! parsedline 'line (port-line port))) + ; TODO: If the line is empty. Either do it here and do not add it, just + ; increment the empty line counter, or strip it later. Replace indent + ; -1 by indent 0 afterwards. + (loop + (append indent-and-symbols (list parsedline)) + #t ; inindent + (if (<= 2 emptylines) + #f ; chunk ends here + (equal? #\_ (peek-char port))); are we in underscore indent? + #f ; incomment + 0 + '() + emptylines))) + ((equal? #t incomment) + (read-char port); remove one comment character + (loop + indent-and-symbols + #f ; inindent + #f ; inunderscoreindent + #t ; incomment + currentindent + currentsymbols + emptylines)) + ((or (equal? #\space next-char) (equal? #\tab next-char) (equal? #\return next-char)); remove whitespace when not in indent + (read-char port); remove char + (loop + indent-and-symbols + #f ; inindent + #f ; inunderscoreindent + #f ; incomment + currentindent + currentsymbols + emptylines)) + ; | cludge to appease the former wisp parser + ; | used for bootstrapping which has a + ; v problem with the literal comment char + ((equal? (string-ref ";" 0) next-char) + (loop + indent-and-symbols + #f ; inindent + #f ; inunderscoreindent + #t ; incomment + currentindent + currentsymbols + emptylines)) + (else ; use the reader + (loop + indent-and-symbols + #f ; inindent + #f ; inunderscoreindent + #f ; incomment + currentindent + ; this also takes care of the hashbang and leading comments. + (append currentsymbols (list (wisp-read port))) + emptylines)))))))) + + +(define (line-code-replace-inline-colons line) + "Replace inline colons by opening parens which close at the end of the line" + ; format #t "replace inline colons for line ~A\n" line + (let loop + ((processed '()) + (unprocessed line)) + (cond + ((null? unprocessed) + ; format #t "inline-colons processed line: ~A\n" processed + processed) + ; replace : . with nothing + ((and (<= 2 (length unprocessed)) (equal? readcolon (car unprocessed)) (equal? repr-dot (car (cdr unprocessed)))) + (loop + (append processed + (loop '() (cdr (cdr unprocessed)))) + '())) + ((equal? readcolon (car unprocessed)) + (loop + ; FIXME: This should turn unprocessed into a list. + (append processed + (list (loop '() (cdr unprocessed)))) + '())) + (else + (loop + (append processed + (list (car unprocessed))) + (cdr unprocessed)))))) + +(define (line-replace-inline-colons line) + (cons + (line-indent line) + (line-code-replace-inline-colons (line-code line)))) + +(define (line-strip-lone-colon line) + "A line consisting only of a colon is just a marked indentation level. We need to kill the colon before replacing inline colons." + (if + (equal? + (line-code line) + (list readcolon)) + (list (line-indent line)) + line)) + +(define (line-finalize line) + "Process all wisp-specific information in a line and strip it" + (let ((l (line-code-replace-inline-colons + (line-strip-indentation-marker + (line-strip-lone-colon + (line-strip-continuation line)))))) + (when (not (null? (source-properties line))) + (catch #t + (lambda () + (set-source-properties! l (source-properties line))) + (lambda (key . arguments) + #f))) + l)) + +(define (wisp-add-source-properties-from source target) + "Copy the source properties from source into the target and return the target." + (catch #t + (lambda () + (set-source-properties! target (source-properties source))) + (lambda (key . arguments) + #f)) + target) + +(define (wisp-propagate-source-properties code) + "Propagate the source properties from the sourrounding list into every part of the code." + (let loop + ((processed '()) + (unprocessed code)) + (cond + ((and (null? processed) (not (pair? unprocessed)) (not (list? unprocessed))) + unprocessed) + ((and (pair? unprocessed) (not (list? unprocessed))) + (cons + (wisp-propagate-source-properties (car unprocessed)) + (wisp-propagate-source-properties (cdr unprocessed)))) + ((null? unprocessed) + processed) + (else + (let ((line (car unprocessed))) + (if (null? (source-properties unprocessed)) + (wisp-add-source-properties-from line unprocessed) + (wisp-add-source-properties-from unprocessed line)) + (loop + (append processed (list (wisp-propagate-source-properties line))) + (cdr unprocessed))))))) + +(define* (wisp-scheme-indentation-to-parens lines) + "Add parentheses to lines and remove the indentation markers" + (when + (and + (not (null? lines)) + (not (line-empty-code? (car lines))) + (not (= 0 (line-real-indent (car lines))))); -1 is a line with a comment + (if (= 1 (line-real-indent (car lines))) + ;; accept a single space as indentation of the first line (and ignore the indentation) to support meta commands + (set! lines + (cons + (cons 0 (cdr (car lines))) + (cdr lines))) + (throw 'wisp-syntax-error + (format #f "The first symbol in a chunk must start at zero indentation. Indentation and line: ~A" + (car lines))))) + (let loop + ((processed '()) + (unprocessed lines) + (indentation-levels '(0))) + (let* + ((current-line + (if (<= 1 (length unprocessed)) + (car unprocessed) + (list 0))); empty code + (next-line + (if (<= 2 (length unprocessed)) + (car (cdr unprocessed)) + (list 0))); empty code + (current-indentation + (car indentation-levels)) + (current-line-indentation (line-real-indent current-line))) + ; format #t "processed: ~A\ncurrent-line: ~A\nnext-line: ~A\nunprocessed: ~A\nindentation-levels: ~A\ncurrent-indentation: ~A\n\n" + ; . processed current-line next-line unprocessed indentation-levels current-indentation + (cond + ; the real end: this is reported to the outside world. + ((and (null? unprocessed) (not (null? indentation-levels)) (null? (cdr indentation-levels))) + ; display "done\n" + ; reverse the processed lines, because I use cons. + processed) + ; the recursion end-condition + ((and (null? unprocessed)) + ; display "last step\n" + ; this is the last step. Nothing more to do except + ; for rolling up the indentation levels. return the + ; new processed and unprocessed lists: this is a + ; side-recursion + (values processed unprocessed)) + ((null? indentation-levels) + ; display "indentation-levels null\n" + (throw 'wisp-programming-error "The indentation-levels are null but the current-line is null: Something killed the indentation-levels.")) + (else ; now we come to the line-comparisons and indentation-counting. + (cond + ((line-empty-code? current-line) + ; display "current-line empty\n" + ; We cannot process indentation without + ; code. Just switch to the next line. This should + ; only happen at the start of the recursion. + ; TODO: Somehow preserve the line-numbers. + (loop + processed + (cdr unprocessed) + indentation-levels)) + ((and (line-empty-code? next-line) (<= 2 (length unprocessed))) + ; display "next-line empty\n" + ; TODO: Somehow preserve the line-numbers. + ; take out the next-line from unprocessed. + (loop + processed + (cons current-line + (cdr (cdr unprocessed))) + indentation-levels)) + ((> current-indentation current-line-indentation) + ; display "current-indent > next-line\n" + ; this just steps back one level via the side-recursion. + (let ((previous-indentation (car (cdr indentation-levels)))) + (if (<= current-line-indentation previous-indentation) + (values processed unprocessed) + (begin ;; not yet used level! TODO: maybe throw an error here instead of a warning. + (let ((linenumber (- (length lines) (length unprocessed)))) + (format (current-error-port) ";;; WARNING:~A: used lower but undefined indentation level (line ~A of the current chunk: ~S). This makes refactoring much more error-prone, therefore it might become an error in a later version of Wisp.\n" (source-property current-line 'line) linenumber (cdr current-line))) + (loop + processed + unprocessed + (cons ; recursion via the indentation-levels + current-line-indentation + (cdr indentation-levels))))))) + ((= current-indentation current-line-indentation) + ; display "current-indent = next-line\n" + (let + ((line (line-finalize current-line)) + (next-line-indentation (line-real-indent next-line))) + (cond + ((>= current-line-indentation next-line-indentation) + ; simple recursiive step to the next line + ; display "current-line-indent >= next-line-indent\n" + (loop + (append processed + (if (line-continues? current-line) + line + (wisp-add-source-properties-from line (list line)))) + (cdr unprocessed); recursion here + indentation-levels)) + ((< current-line-indentation next-line-indentation) + ; display "current-line-indent < next-line-indent\n" + ; format #t "line: ~A\n" line + ; side-recursion via a sublist + (let-values + (((sub-processed sub-unprocessed) + (loop + line + (cdr unprocessed); recursion here + indentation-levels))) + ; format #t "side-recursion:\n sub-processed: ~A\n processed: ~A\n\n" sub-processed processed + (loop + (append processed (list sub-processed)) + sub-unprocessed ; simply use the recursion from the sub-recursion + indentation-levels)))))) + ((< current-indentation current-line-indentation) + ; display "current-indent < next-line\n" + (loop + processed + unprocessed + (cons ; recursion via the indentation-levels + current-line-indentation + indentation-levels))) + (else + (throw 'wisp-not-implemented + (format #f "Need to implement further line comparison: current: ~A, next: ~A, processed: ~A." + current-line next-line processed))))))))) + + +(define (wisp-scheme-replace-inline-colons lines) + "Replace inline colons by opening parens which close at the end of the line" + (let loop + ((processed '()) + (unprocessed lines)) + (if (null? unprocessed) + processed + (loop + (append processed (list (line-replace-inline-colons (car unprocessed)))) + (cdr unprocessed))))) + + +(define (wisp-scheme-strip-indentation-markers lines) + "Strip the indentation markers from the beginning of the lines" + (let loop + ((processed '()) + (unprocessed lines)) + (if (null? unprocessed) + processed + (loop + (append processed (cdr (car unprocessed))) + (cdr unprocessed))))) + +(define (wisp-unescape-underscore-and-colon code) + "replace \\_ and \\: by _ and :" + (cond ((list? code) (map wisp-unescape-underscore-and-colon code)) + ((eq? code '\:) ':) + ;; Look for symbols like \____ and remove the \. + ((symbol? code) + (let ((as-string (symbol->string code))) + (if (and (>= (string-length as-string) 2) ; at least a single underscore + (char=? (string-ref as-string 0) #\\) + (string-every #\_ (substring as-string 1))) + (string->symbol (substring as-string 1)) + code))) + (#t code))) + + +(define (wisp-replace-empty-eof code) + "replace ((#)) by ()" + ; FIXME: Actually this is a hack which fixes a bug when the + ; parser hits files with only hashbang and comments. + (if (and (not (null? code)) (pair? (car code)) (eof-object? (car (car code))) (null? (cdr code)) (null? (cdr (car code)))) + (list) + code)) + + +(define (wisp-replace-paren-quotation-repr code) + "Replace lists starting with a quotation symbol by + quoted lists." + (match code + (('REPR-QUOTE-e749c73d-c826-47e2-a798-c16c13cb89dd a ...) + (list 'quote (map wisp-replace-paren-quotation-repr a))) + ((a ... 'REPR-QUOTE-e749c73d-c826-47e2-a798-c16c13cb89dd b); this is the quoted empty list + (append + (map wisp-replace-paren-quotation-repr a) + (list (list 'quote (map wisp-replace-paren-quotation-repr b))))) + (('REPR-QUASIQUOTE-e749c73d-c826-47e2-a798-c16c13cb89dd 'REPR-UNQUOTE-e749c73d-c826-47e2-a798-c16c13cb89dd a ...) + (list 'quasiquote (list 'unquote (map wisp-replace-paren-quotation-repr a)))) + (('REPR-UNQUOTE-e749c73d-c826-47e2-a798-c16c13cb89dd a ...) + (list 'unquote (map wisp-replace-paren-quotation-repr a))) + ((a ... 'REPR-UNQUOTE-e749c73d-c826-47e2-a798-c16c13cb89dd b) + (append + (map wisp-replace-paren-quotation-repr a) + (list (list 'unquote (map wisp-replace-paren-quotation-repr b))))) + (('REPR-QUASIQUOTE-e749c73d-c826-47e2-a798-c16c13cb89dd a ...) + (list 'quasiquote (map wisp-replace-paren-quotation-repr a))) + ((a ... 'REPR-QUASIQUOTE-e749c73d-c826-47e2-a798-c16c13cb89dd b); this is the quoted empty list + (append + (map wisp-replace-paren-quotation-repr a) + (list (list 'quasiquote (map wisp-replace-paren-quotation-repr b))))) + (('REPR-UNQUOTESPLICING-e749c73d-c826-47e2-a798-c16c13cb89dd a ...) + (list 'unquote-splicing (map wisp-replace-paren-quotation-repr a))) + (('REPR-SYNTAX-e749c73d-c826-47e2-a798-c16c13cb89dd a ...) + (list 'syntax (map wisp-replace-paren-quotation-repr a))) + (('REPR-UNSYNTAX-e749c73d-c826-47e2-a798-c16c13cb89dd a ...) + (list 'unsyntax (map wisp-replace-paren-quotation-repr a))) + (('REPR-QUASISYNTAX-e749c73d-c826-47e2-a798-c16c13cb89dd a ...) + (list 'quasisyntax (map wisp-replace-paren-quotation-repr a))) + (('REPR-UNSYNTAXSPLICING-e749c73d-c826-47e2-a798-c16c13cb89dd a ...) + (list 'unsyntax-splicing (map wisp-replace-paren-quotation-repr a))) + ;; literal array as start of a line: # (a b) c -> (#(a b) c) + ((#\# a ...) + (with-input-from-string ;; hack to defer to read + (string-append "#" + (with-output-to-string + (λ () + (write (map wisp-replace-paren-quotation-repr a) + (current-output-port))))) + read)) + ((a ...) + (map wisp-replace-paren-quotation-repr a)) + (a + a))) + +(define (wisp-make-improper code) + "Turn (a #{.}# b) into the correct (a . b). + +read called on a single dot creates a variable named #{.}# (|.| +in r7rs). Due to parsing the indentation before the list +structure is known, the reader cannot create improper lists +when it reads a dot. So we have to take another pass over the +code to recreate the improper lists. + +Match is awesome!" + (let + ((improper + (match code + ((a ... b 'REPR-DOT-e749c73d-c826-47e2-a798-c16c13cb89dd c) + (append (map wisp-make-improper a) + (cons (wisp-make-improper b) (wisp-make-improper c)))) + ((a ...) + (map wisp-make-improper a)) + (a + a)))) + (define (syntax-error li msg) + (throw 'wisp-syntax-error (format #f "incorrect dot-syntax #{.}# in code: ~A: ~A" msg li))) + (if #t + improper + (let check + ((tocheck improper)) + (match tocheck + ; lists with only one member + (('REPR-DOT-e749c73d-c826-47e2-a798-c16c13cb89dd) + (syntax-error tocheck "list with the period as only member")) + ; list with remaining dot. + ((a ...) + (if (and (member repr-dot a)) + (syntax-error tocheck "leftover period in list") + (map check a))) + ; simple pair - this and the next do not work when parsed from wisp-scheme itself. Why? + (('REPR-DOT-e749c73d-c826-47e2-a798-c16c13cb89dd . c) + (syntax-error tocheck "dot as first element in already improper pair")) + ; simple pair, other way round + ((a . 'REPR-DOT-e749c73d-c826-47e2-a798-c16c13cb89dd) + (syntax-error tocheck "dot as last element in already improper pair")) + ; more complex pairs + ((? pair? a) + (let + ((head (drop-right a 1)) + (tail (last-pair a))) + (cond + ((equal? repr-dot (car tail)) + (syntax-error tocheck "equal? repr-dot : car tail")) + ((equal? repr-dot (cdr tail)) + (syntax-error tocheck "equal? repr-dot : cdr tail")) + ((member repr-dot head) + (syntax-error tocheck "member repr-dot head")) + (else + a)))) + (a + a)))))) + +(define (wisp-scheme-read-chunk port) + "Read and parse one chunk of wisp-code" + (with-fluids ((%read-hash-procedures (fluid-ref %read-hash-procedures))) + (read-hash-extend #\# (lambda args #\#)) + (let ((lines (wisp-scheme-read-chunk-lines port))) + (wisp-make-improper + (wisp-replace-empty-eof + (wisp-unescape-underscore-and-colon + (wisp-replace-paren-quotation-repr + (wisp-propagate-source-properties + (wisp-scheme-indentation-to-parens lines))))))))) + +(define (wisp-scheme-read-all port) + "Read all chunks from the given port" + (let loop + ((tokens '())) + (cond + ((eof-object? (peek-char port)) + tokens) + (else + (loop + (append tokens (wisp-scheme-read-chunk port))))))) + +(define (wisp-scheme-read-file path) + (call-with-input-file path wisp-scheme-read-all)) + +(define (wisp-scheme-read-file-chunk path) + (call-with-input-file path wisp-scheme-read-chunk)) + +(define (wisp-scheme-read-string str) + (call-with-input-string str wisp-scheme-read-all)) + +(define (wisp-scheme-read-string-chunk str) + (call-with-input-string str wisp-scheme-read-chunk)) + diff --git a/module/language/wisp/spec.scm b/module/language/wisp/spec.scm new file mode 100644 index 000000000..477036c71 --- /dev/null +++ b/module/language/wisp/spec.scm @@ -0,0 +1,85 @@ +;; Language interface for Wisp in Guile + +;;; adapted from guile-sweet: https://gitorious.org/nacre/guile-sweet/source/ae306867e371cb4b56e00bb60a50d9a0b8353109:sweet/common.scm + +;;; Copyright (C) 2005--2014 by David A. Wheeler and Alan Manuel K. Gloria +;;; Copyright (C) 2014--2023 Arne Babenhauserheide. +;;; Copyright (C) 2023 Maxime Devos + +;;; Permission is hereby granted, free of charge, to any person +;;; obtaining a copy of this software and associated documentation +;;; files (the "Software"), to deal in the Software without +;;; restriction, including without limitation the rights to use, copy, +;;; modify, merge, publish, distribute, sublicense, and/or sell copies +;;; of the Software, and to permit persons to whom the Software is +;;; furnished to do so, subject to the following conditions: +;;; +;;; The above copyright notice and this permission notice shall be +;;; included in all copies or substantial portions of the Software. +;;; +;;; THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, +;;; EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF +;;; MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND +;;; NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS +;;; BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN +;;; ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN +;;; CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE +;;; SOFTWARE. + +; adapted from spec.scm: https://gitorious.org/nacre/guile-sweet/source/ae306867e371cb4b56e00bb60a50d9a0b8353109:sweet/spec.scm +(define-module (language wisp spec) + #:use-module (language wisp) + #:use-module (system base compile) + #:use-module (system base language) + #:use-module (language scheme compile-tree-il) + #:use-module (language scheme decompile-tree-il) + #:export (wisp)) + +;;; +;;; Language definition +;;; + + +(define (read-one-wisp-sexp port env) + ;; Allow using "# foo" as #(foo). + ;; Don't use the globally-acting read-hash-extend, because this + ;; doesn't make much sense in parenthese-y (non-Wisp) Scheme. + ;; Instead, use fluids to temporarily add the extension. + (with-fluids ((%read-hash-procedures (fluid-ref %read-hash-procedures))) + (read-hash-extend #\# (lambda args #\# )) + ;; Read Wisp files as UTF-8, to support non-ASCII characters. + ;; TODO: would be nice to support ';; coding: whatever' lines + ;; like in parenthese-y Scheme. + (set-port-encoding! port "UTF-8") + (if (eof-object? (peek-char port)) + (read-char port) ; return eof: we’re done + (let ((chunk (wisp-scheme-read-chunk port))) + (and (not (null? chunk)) ; <---- XXX: maybe (pair? chunk) + (car chunk)))))) + +(define-language wisp + #:title "Wisp Scheme Syntax. See SRFI-119 for details." + ; . #:reader read-one-wisp-sexp + #:reader read-one-wisp-sexp ; : lambda (port env) : let ((x (read-one-wisp-sexp port env))) (display x)(newline) x ; + #:compilers `((tree-il . ,compile-tree-il)) + #:decompilers `((tree-il . ,decompile-tree-il)) + #:evaluator (lambda (x module) (primitive-eval x)) + #:printer write ; TODO: backtransform to wisp? Use source-properties? + #:make-default-environment + (lambda () + ;; Ideally we'd duplicate the whole module hierarchy so that `set!', + ;; `fluid-set!', etc. don't have any effect in the current environment. + (let ((m (make-fresh-user-module))) + ;; Provide a separate `current-reader' fluid so that + ;; compile-time changes to `current-reader' are + ;; limited to the current compilation unit. + (module-define! m 'current-reader (make-fluid)) + ;; Default to `simple-format', as is the case until + ;; (ice-9 format) is loaded. This allows + ;; compile-time warnings to be emitted when using + ;; unsupported options. + (module-set! m 'format simple-format) + m))) + + + diff --git a/test-suite/tests/srfi-119.test b/test-suite/tests/srfi-119.test new file mode 100644 index 000000000..a888df41d --- /dev/null +++ b/test-suite/tests/srfi-119.test @@ -0,0 +1,81 @@ +;;;; srfi-119.test --- Test suite for Guile's SRFI-119 reader. -*- scheme -*- +;;;; +;;;; Copyright (C) 2023 Free Software Foundation, Inc. +;;;; +;;;; This library is free software; you can redistribute it and/or +;;;; modify it under the terms of the GNU Lesser General Public +;;;; License as published by the Free Software Foundation; either +;;;; version 3 of the License, or (at your option) any later version. +;;;; +;;;; This library is distributed in the hope that it will be useful, +;;;; but WITHOUT ANY WARRANTY; without even the implied warranty of +;;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +;;;; Lesser General Public License for more details. +;;;; +;;;; You should have received a copy of the GNU Lesser General Public +;;;; License along with this library; if not, write to the Free Software +;;;; Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + +(define-module (test-srfi-119) + #:use-module (test-suite lib) + #:use-module (srfi srfi-1) + #:use-module (language wisp)) + +(define (read-string s) + (with-input-from-string s read)) + +(define (with-read-options opts thunk) + (let ((saved-options (read-options))) + (dynamic-wind + (lambda () + (read-options opts)) + thunk + (lambda () + (read-options saved-options))))) + +(define (wisp->list str) + (wisp-scheme-read-string str)) + +(with-test-prefix "wisp-read-simple" + (pass-if (equal? (wisp->list "<= n 5") '((<= n 5)))) + (pass-if (equal? (wisp->list ". 5") '(5))) + (pass-if (equal? (wisp->list "+ 1 : * 2 3") '((+ 1 (* 2 3)))))) +(with-test-prefix "wisp-read-complex" + (pass-if (equal? (wisp->list " +a b c d e + . f g h + . i j k + +concat \"I want \" + getwish from me + . \" - \" username +") '( +(a b c d e + f g h + i j k) + +(concat "I want " + (getwish from me) + " - " username)))) + + (pass-if (equal? (wisp->list " +define : a b c +_ d e +___ f +___ g h +__ . i + +define : _ +_ display \"hello\n\" + +\\_") '( +(define (a b c) + (d e + (f) + (g h) + i)) + +(define (_) + (display "hello\n")) + +(_))))) -- 2.39.2