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| -rw-r--r-- | CHANGELOG.md | 12 | ||||
| -rw-r--r-- | COPYING | 674 | ||||
| -rw-r--r-- | README.md | 36 | ||||
| -rw-r--r-- | infix-to-scheme.scm | 272 | ||||
| -rw-r--r-- | infix-to-scheme/rule-set.scm | 184 |
5 files changed, 1178 insertions, 0 deletions
diff --git a/CHANGELOG.md b/CHANGELOG.md new file mode 100644 index 0000000..3ed6e1c --- /dev/null +++ b/CHANGELOG.md @@ -0,0 +1,12 @@ +# ChangeLog + +The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/), +and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html). + +## [Unreleased] + +- Add README.md file. +- Add COPYING file. +- Add `(infix-to-scheme)` module. +- Add `(infix-to-scheme rule-set)` module. +- Add CHANGELOG.md file. @@ -0,0 +1,674 @@ + GNU GENERAL PUBLIC LICENSE + Version 3, 29 June 2007 + + Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/> + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + Preamble + + The GNU General Public License is a free, copyleft license for +software and other kinds of works. + + The licenses for most software and other practical works are designed +to take away your freedom to share and change the works. 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If not, see <https://www.gnu.org/licenses/>. + +Also add information on how to contact you by electronic and paper mail. + + If the program does terminal interaction, make it output a short +notice like this when it starts in an interactive mode: + + <program> Copyright (C) <year> <name of author> + This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. + This is free software, and you are welcome to redistribute it + under certain conditions; type `show c' for details. + +The hypothetical commands `show w' and `show c' should show the appropriate +parts of the General Public License. Of course, your program's commands +might be different; for a GUI interface, you would use an "about box". + + You should also get your employer (if you work as a programmer) or school, +if any, to sign a "copyright disclaimer" for the program, if necessary. +For more information on this, and how to apply and follow the GNU GPL, see +<https://www.gnu.org/licenses/>. + + The GNU General Public License does not permit incorporating your program +into proprietary programs. If your program is a subroutine library, you +may consider it more useful to permit linking proprietary applications with +the library. If this is what you want to do, use the GNU Lesser General +Public License instead of this License. But first, please read +<https://www.gnu.org/licenses/why-not-lgpl.html>. diff --git a/README.md b/README.md new file mode 100644 index 0000000..54b9000 --- /dev/null +++ b/README.md @@ -0,0 +1,36 @@ +# Infix-to-Scheme + +Infix-to-Scheme is an R7RS library for converting infix formula to Scheme expression. + +## Usage + +### Import `(infix-to-scheme)` library + +```scheme +(import (infix-to-scheme)) +``` + +#### `(infix->scheme expr) → <sexpr>` + +Returns converted scheme expression if `expr` is a valid infix formula expression; otherwise, it returns`#f`. + +#### `(scheme->infix expr) → <sexpr>` + +Returns converted infix formula expression if `expr` is a valid scheme expression; otherwise, it returns`#f`. + +## Downloading code with git + +Use git command. + +```shell +git clone https://git.tojo.tokyo/infix-to-scheme.git +``` + +## License + +This library is released under the GPLv3+ License. +See the COPYING file for more details. + +## Copyright + +Copyright (c) 2024 Masaya Tojo <masaya@tojo.tokyo> diff --git a/infix-to-scheme.scm b/infix-to-scheme.scm new file mode 100644 index 0000000..ae2fc56 --- /dev/null +++ b/infix-to-scheme.scm @@ -0,0 +1,272 @@ +;;; Infix-to-Scheme --- Library for converting infix formula to Scheme expression +;;; Copyright © 2024 Masaya Tojo <masaya@tojo.tokyo> +;;; +;;; This file is part of Infix-to-Scheme. +;;; +;;; Infix-to-Scheme is free software: you can redistribute it and/or +;;; modify it under the terms of the GNU General Public License as +;;; published by the Free Software Foundation, either version 3 of the +;;; License, or (at your option) any later version. +;;; +;;; Infix-to-Scheme 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 +;;; General Public License for more details. +;;; +;;; You should have received a copy of the GNU General Public License +;;; along with Infix-to-Scheme. If not, see +;;; <https://www.gnu.org/licenses/>. + +(define-library (infix-to-scheme) + (export infix->scheme + scheme->infix + current-operator-rule-set) + (import (scheme base) + (scheme case-lambda) + (infix-to-scheme rule-set) + (only (srfi 1) car+cdr fold break! reverse! append! append-map! append-reverse!) + (only (srfi 26) cut cute)) + (begin + (define (make-default-operator-rule-set) + (rule-set + (list + (operator '= 0) + (operator '+ 1 (direction 'left #t) (identity 0)) + (operator '- 1 (direction 'left) (identity 0 #t #t 3)) + (operator '* 2 (direction 'left #t) (identity 1)) + (operator '/ 2 (direction 'left) (identity 1 #t)) + (operator '^ 4 (direction 'right) #f (scheme #t 'expt))))) + + (define current-operator-rule-set + (make-parameter (make-default-operator-rule-set))) + + (define infix->scheme + (case-lambda + ((expr failure) + (call/cc + (lambda (return) + (let ((rs (current-operator-rule-set))) + (map-all-list (cute infix->scheme-1 <> rs (lambda (e) (return (failure e)))) + expr))))) + ((expr) + (infix->scheme expr (lambda (e) #f))))) + + (define (infix->scheme-1 expr rs fail) + (cond ((and (pair? expr) (null? (cdr expr))) (car expr)) + ((minimum-precedence expr rs) + => (lambda (op) + (let ->scheme ((expr (list-copy expr)) + (op op)) + (define (make-scheme left op-sym right) + (define (->infix left op-sym right) + (append left (cons op-sym right))) + (let ((left-op (minimum-precedence left rs)) + (right-op (minimum-precedence right rs)) + (not-binary-only? (not (operator-scheme-binary-only? op)))) + `(,(operator-scheme-symbol op) + ,@(if (operator? left-op) + (if (eqv? (operator-symbol op) (operator-symbol left-op)) + (if not-binary-only? + (if (and (eqv? op-sym (car left)) + (pair? (cdr left)) + (null? (cdr (cdr left)))) + (list (->scheme left left-op)) + (cdr (->scheme left left-op))) + (if (operator-left? op) + (list (->scheme left left-op)) + (fail expr))) + (list (->scheme left left-op))) + (if (and (pair? left) + (null? (cdr left))) + (if (and not-binary-only? + (or (operator-left? op) + (operator-associative? op)) + (pair? (car left)) + (eqv? (operator-symbol op) (car (car left)))) + (cdr (car left)) + (list (car left))) + (fail (->infix left op-sym right)))) + ,@(if (operator? right-op) + (if (eqv? (operator-symbol op) (operator-symbol right-op)) + (if not-binary-only? + (cdr (->scheme right right-op)) + (if (operator-right? op) + (list (->scheme right right-op)) + (fail expr))) + (list (->scheme right right-op))) + (if (and (pair? right) + (null? (cdr right))) + (if (and not-binary-only? + (or (operator-right? op) + (operator-associative? op)) + (pair? (car right)) + (eqv? (operator-symbol op) (car (car right)))) + (cdr (car right)) + (list (car right))) + (fail (->infix left op-sym right))))))) + (cond ((operator-left? op) + (let ((rev-expr (reverse! expr))) + (let-values (((rev-lst op+rev-rest) (break! (cute eqv? (operator-symbol op) <>) rev-expr))) + (let-values (((op-sym rev-rest) (car+cdr op+rev-rest))) + (if (and (or (null? rev-rest) + (rule-set-infix-ref rs (car rev-rest))) + (and (pair? rev-lst) + (null? (cdr rev-lst)))) + (infix->scheme-1 (append-reverse! rev-rest + (list `(,op-sym ,(car rev-lst)))) + rs + fail) + (make-scheme (reverse! rev-rest) op-sym (reverse! rev-lst))))))) + (else + (let-values (((lst op+rest) (break! (cute eqv? (operator-symbol op) <>) expr))) + (let-values (((op rest) (car+cdr op+rest))) + (make-scheme lst op rest)))))))) + (else expr))) + + (define scheme->infix + (case-lambda + ((expr failure) + (let ((rs (current-operator-rule-set))) + (call-with-current-continuation + (lambda (return) + (let-values (((result _precedence) (%scheme->infix expr rs (lambda (e) (return (failure e)))))) + result))))) + ((expr) + (scheme->infix expr (lambda (e) #f))))) + + (define (%scheme->infix expr rs failure) + (let ->infix ((expr expr)) + (define (->infix-fst expr) + (let-values (((x _) (->infix expr))) + x)) + (if (not (pair? expr)) + (values expr -inf.0) + (let-values (((op-scheme-sym args) (car+cdr expr))) + (cond ((rule-set-scheme-ref rs op-scheme-sym) + => (lambda (op) + (let ((p (operator-precedence op)) + (op-sym (operator-symbol op))) + (cond ((null? args) + (cond ((and (not (operator-identity-inv? op)) + (operator-identity op)) + => (lambda (u) (values (identity-value u) -inf.0))) + (else (failure expr)))) + ((null? (cdr args)) + (let-values (((r-expr r-p) (->infix (car args)))) + (cond ((operator-identity op) + => (lambda (u) + (if (identity-inv? u) + (if (identity-unary? u) + (values `(,op-sym ,r-expr) + (or (operator-identity-unary-precedence op) + +inf.0)) + (values `(,(identity-value (operator-identity op)) + ,op-sym + ,@(if (or (operator-right? op) + (operator-associative? op)) + (wrap-when (< r-p p) r-expr) + (wrap-when (<= r-p p) r-expr))) + p)) + (values r-expr r-p)))) + (else (failure expr))))) + ((null? (cdr (cdr args))) + (let-values (((l-expr l-p) (->infix (car args))) + ((r-expr r-p) (->infix (cadr args)))) + (values `(,@(if (or (operator-left? op) + (operator-associative? op)) + (wrap-when (< l-p p) l-expr) + (wrap-when (<= l-p p) l-expr)) + ,op-sym + ,@(if (or (operator-right? op) + (operator-associative? op)) + (wrap-when (< r-p p) r-expr) + (wrap-when (<= r-p p) r-expr))) + p))) + (else + (cond ((operator-associative? op) + (values (cdr (append-map! (lambda (arg) + (let-values (((x-expr x-p) (->infix arg))) + (cons op-sym (wrap-when (< x-p p) x-expr)))) + args)) + p)) + ((operator-left? op) + (let-values (((l-expr l-p) (->infix (car args)))) + (values (append! (wrap-when (< l-p p) l-expr) + (append-map! (lambda (arg) + (let-values (((l-expr l-p) (->infix arg))) + (cons op-sym (wrap-when (<= l-p p) l-expr)))) + (cdr args))) + p))) + ((operator-right? op) + (let ((rev-args (reverse args))) + (let-values (((r-expr r-p) (->infix (car rev-args)))) + (values (reverse! + (append-reverse! (wrap-when (< r-p p) r-expr) + (append-map! + (lambda (arg) + (let-values (((r-expr r-p) (->infix arg))) + (cons op-sym (wrap-when (<= r-p p) r-expr)))) + (cdr rev-args)))) + p)))) + (else + (values (cdr (append-map! (lambda (arg) + (let-values (((x-expr x-p) (->infix arg))) + (cons op-sym (wrap-when (<= x-p p) x-expr)))) + args)) + p)))))))) + (else (values (map ->infix-fst expr) -inf.0))))))) + + (define (minimum-precedence expr rs) + (let loop ((expr expr) + (min #f) + (min-precedence +inf.0) + (prev #t)) + (if (null? expr) + min + (cond ((rule-set-infix-ref rs (car expr)) + => (lambda (current) + (let ((precedence + (if (and (operator-identity-unary? current) + prev) + (operator-identity-unary-precedence current) + (operator-precedence current)))) + (if (<= precedence min-precedence) + (loop (cdr expr) current precedence current) + (loop (cdr expr) min min-precedence current))))) + (else (loop (cdr expr) min min-precedence #f)))))) + + (define (operator-identity-inv? x) + (cond ((operator-identity x) => (cut identity-inv? <>)) + (else #f))) + + (define (operator-identity-unary? op) + (cond ((operator-identity op) => identity-unary?) + (else #f))) + + (define (operator-identity-unary-precedence op) + (cond ((operator-identity op) => + (lambda (id) + (cond ((identity-unary-precedence id) + => (lambda (p) p)) + (else (operator-precedence op))))) + (else #f))) + + (define (operator-scheme-binary-only? op) + (cond ((operator-scheme op) => scheme-binary-only?) + (else #f))) + + (define (wrap-when b? x) + (if b? (list x) x)) + + (define (map-all-list f expr) + (f (map-cars f expr))) + + (define (map-cars f expr) + (if (pair? expr) + (if (pair? (car expr)) + (cons (f (map-cars f (car expr))) + (map-cars f (cdr expr))) + (cons (car expr) + (map-cars f (cdr expr)))) + expr)) + )) diff --git a/infix-to-scheme/rule-set.scm b/infix-to-scheme/rule-set.scm new file mode 100644 index 0000000..22ffcc3 --- /dev/null +++ b/infix-to-scheme/rule-set.scm @@ -0,0 +1,184 @@ +;;; Infix-to-Scheme --- Library for converting infix formula to Scheme expression +;;; Copyright © 2024 Masaya Tojo <masaya@tojo.tokyo> +;;; +;;; This file is part of Infix-to-Scheme. +;;; +;;; Infix-to-Scheme is free software: you can redistribute it and/or +;;; modify it under the terms of the GNU General Public License as +;;; published by the Free Software Foundation, either version 3 of the +;;; License, or (at your option) any later version. +;;; +;;; Infix-to-Scheme 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 +;;; General Public License for more details. +;;; +;;; You should have received a copy of the GNU General Public License +;;; along with Infix-to-Scheme. If not, see +;;; <https://www.gnu.org/licenses/>. + +(define-library (infix-to-scheme rule-set) + (export rule-set + rule-set? + rule-set-infix-ref + rule-set-scheme-ref + + operator + operator? + operator-symbol + operator-scheme-symbol + operator-precedence + operator-left? + operator-right? + operator-associative? + operator-scheme + operator-identity + + identity + identity? + identity-value + identity-inv? + identity-unary? + identity-unary-precedence + + direction + direction? + direction-left? + direction-associative? + + scheme + scheme? + scheme-symbol + scheme-binary-only?) + (import (scheme base) + (scheme case-lambda) + (only (srfi 128) make-eqv-comparator)) + (cond-expand + ((library (srfi srfi-146 hash)) ;; for guile-srfi-146 + (import (only (srfi srfi-146 hash) hashmap-ref/default hashmap-unfold))) + ((library (srfi 146 hash)) + (import (only (srfi 146 hash) hashmap-ref/default hashmap-unfold)))) + (begin + (define-record-type <rule-set> + (make-rule-set operator-hashmap scheme-hashmap) + rule-set? + (operator-hashmap rule-set-operator-hashmap) + (scheme-hashmap rule-set-scheme-hashmap)) + + (define (rule-set operator-list) + (make-rule-set (list->operator-hashmap operator-list) + (list->scheme-hashmap operator-list))) + + (define (list->operator-hashmap ops) + (hashmap-unfold null? + (lambda (ops) + (values (operator-symbol (car ops)) + (car ops))) + cdr + ops + (make-eqv-comparator))) + + (define (list->scheme-hashmap ops) + (hashmap-unfold null? + (lambda (ops) + (let ((op (car ops))) + (values (operator-scheme-symbol op) + (car ops)))) + cdr + ops + (make-eqv-comparator))) + + (define (rule-set-infix-ref rule-set key) + (hashmap-ref/default (rule-set-operator-hashmap rule-set) key #f)) + + (define (rule-set-scheme-ref rule-set key) + (hashmap-ref/default (rule-set-scheme-hashmap rule-set) key #f)) + + (define-record-type <operator> + (make-operator symbol precedence dir identity scheme) + operator? + (symbol operator-symbol) + (precedence operator-precedence) + (dir operator-direction) + (identity operator-identity) + (scheme operator-scheme)) + + (define operator + (case-lambda + ((symbol precedence) + (operator symbol precedence #f)) + ((symbol precedence direction) + (operator symbol precedence direction #f)) + ((symbol precedence direction identity) + (operator symbol precedence direction identity #f)) + ((symbol precedence direction identity scheme) + (when (and identity (identity-unary? identity) + (not (and direction (direction-left? direction)))) + (error "operator: unary operator must be left direction" symbol)) + (make-operator symbol precedence direction identity scheme)))) + + (define-record-type <direction> + (make-direction left? associative?) + direction? + (left? direction-left?) + (associative? direction-associative?)) + + (define (direction-right? assoc) + (not (direction-left? assoc))) + + (define direction + (case-lambda + ((dir) + (direction dir #f)) + ((dir associative?) + (unless (or (eq? 'left dir) + (eq? 'right dir)) + (error "direction: The 1st argument must be 'left or 'right" dir)) + (make-direction (eq? 'left dir) associative?)))) + + (define (operator-left? x) + (cond ((operator-direction x) => direction-left?) + (else #f))) + + (define (operator-right? x) + (cond ((operator-direction x) => (lambda (a) (not (direction-left? a)))) + (else #f))) + + (define (operator-associative? x) + (cond ((operator-direction x) => direction-associative?) + (else #f))) + + (define (operator-scheme-symbol op) + (cond ((operator-scheme op) => (lambda (p) + (and (scheme-has-symbol? p) + (scheme-symbol p)))) + (else (operator-symbol op)))) + + (define-record-type <scheme> + (make-scheme binary-only? has-symbol? symbol) + scheme? + (binary-only? scheme-binary-only?) + (has-symbol? scheme-has-symbol?) + (symbol scheme-symbol)) + + (define scheme + (case-lambda + ((binary-only?) + (make-scheme binary-only? #f #f)) + ((binary-only? symbol) + (make-scheme binary-only? #t symbol)))) + + (define-record-type <identity> + (make-identity value inv? unary? unary-precedence) + identity? + (value identity-value) + (inv? identity-inv?) + (unary? identity-unary?) + (unary-precedence identity-unary-precedence)) + + (define identity + (case-lambda + ((value) (identity value #f)) + ((value inv?) (identity value inv? #f)) + ((value inv? unary?) (identity value inv? unary? #f)) + ((value inv? unary? unary-precedence) (make-identity value inv? unary? unary-precedence)))))) |