On Wed, Jun 15, 2016 at 03:56:43PM +0200, Ludovic Courtès wrote: > Efraim Flashner <efr...@flashner.co.il> skribis: > > > From 09eef9cd841a7d212e024be0609168611923696b Mon Sep 17 00:00:00 2001 > > From: Efraim Flashner <efr...@flashner.co.il> > > Date: Sun, 22 May 2016 14:56:06 +0300 > > Subject: [PATCH] bournish: Add `wc' command. > > > > * guix/build/bournish.scm (lines+chars, only-files, wc-commands, > > wc-command-implementation, wc-l-command-implementation, > > wc-c-command-implementation): New variables. > > s/variables/procedures/ :-) > > > (%commands): Add wc command. > > [...] > > > +(define (only-files files) > > + (filter (lambda (file) > > + (catch 'system-error > > + (lambda () > > + (stat file)) > > + (lambda args > > + (let ((errno (system-error-errno args))) > > + (format (current-error-port) "~a: ~a~%" > > + file (strerror errno)) > > + #f)))) > > + files)) > > + > > +(define (wc-command-implementation . files) > > + (for-each > > + (lambda (file) > > + (let-values (((lines chars) > > + (call-with-input-file file lines+chars))) > > + (format #t "~a ~a ~a~%" lines chars file))) > > + ((@@ (guix build bournish) only-files) files))) > > I prefer the approach Ricardo suggested, I think it’s more concise and > clearer: > > https://lists.gnu.org/archive/html/guix-devel/2016-06/msg00525.html > > Also, note that @@ would not be needed here; @@ serves to access private > bindings within a specific module: > > https://www.gnu.org/software/guile/manual/html_node/Using-Guile-Modules.html > > Last, do not miss the bit about docstrings at: > > https://www.gnu.org/software/guix/manual/html_node/Formatting-Code.html > > :-) > > With these changes, we’re all set. Thanks!
I've attached another patch > > From a GSoC viewpoint, I think we must move to the compilation part > now. Specifically, I think the next step is to start parsing Bash > code. This part took much longer than I thought it would. Going forward I'll try to be more pro-active on IRC about asking for help. > > For that we could use SILex + parse-lalr, but these are not the nicest > tools for the job. Better tools would be “parsing expression grammars” > (the (ice-9 peg) module in Guile 2.1) or parser combinators, though I > don’t think there’s a directly usable Guile library for that. Maybe > Eric or David can comment? > I get lalr as look-ahead left->right parser and found this¹, but what's SILex? I also found peg in the master branch of the guile manual². > The goal is to have a parser that returns an abstract syntax tree (AST) > as an sexp: > > (parse "(cd /foo; ls $HOME) && echo *.a ; echo done") > => > '(sequence > (success-sequence > (subshell > (sequence (command "cd" "/foo") > (command "ls" (variable-ref "HOME")))) > (command "echo" (glob "*.a"))) > (command "echo" "done")) > > Thoughts? > > Ludo’. ¹ https://www.gnu.org/software/guile/manual/html_node/LALR_00281_0029-Parsing.html#LALR_00281_0029-Parsing ² https://www.gnu.org/software/guile/docs/master/guile.html/PEG-Parsing.html#PEG-Parsing -- Efraim Flashner <efr...@flashner.co.il> אפרים פלשנר GPG key = A28B F40C 3E55 1372 662D 14F7 41AA E7DC CA3D 8351 Confidentiality cannot be guaranteed on emails sent or received unencrypted
From 432d742639e193a29aeedc2f080c349494fa2a8f Mon Sep 17 00:00:00 2001
From: Efraim Flashner <efr...@flashner.co.il>
Date: Sun, 22 May 2016 14:56:06 +0300
Subject: [PATCH] bournish: Add `wc' command.
* guix/build/bournish.scm (lines+chars, only-files, wc-print,
wc-l-print, wc-c-print, wc-commands, wc-command-implementation,
wc-l-command-implementation, wc-c-command-implementation): New procedures.
(%commands): Add wc command.
---
guix/build/bournish.scm | 56 ++++++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 55 insertions(+), 1 deletion(-)
diff --git a/guix/build/bournish.scm b/guix/build/bournish.scm
index 1f17e0a..97c1b43 100644
--- a/guix/build/bournish.scm
+++ b/guix/build/bournish.scm
@@ -1,5 +1,6 @@
;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2016 Ludovic Courtès <l...@gnu.org>
+;;; Copyright © 2016 Efraim Flashner <efr...@flashner.co.il>
;;;
;;; This file is part of GNU Guix.
;;;
@@ -25,6 +26,7 @@
#:use-module (ice-9 match)
#:use-module (ice-9 ftw)
#:use-module (srfi srfi-1)
+ #:use-module (srfi srfi-11)
#:use-module (srfi srfi-26)
#:export (%bournish-language))
@@ -103,6 +105,57 @@ characters."
((@ (guix build utils) dump-port) port (current-output-port))
*unspecified*)))
+(define (lines+chars port)
+ ;; Return the number of lines and number of chars read from PORT.
+ ;; TODO: Also return the number of words.
+ (let loop ((lines 0) (chars 0))
+ (match (read-char port) ; get the next char ready
+ ((? eof-object?) ;done!
+ (values lines chars))
+ (#\newline ;recurse
+ (loop (1+ lines) (1+ chars)))
+ (_ ;recurse
+ (loop lines (1+ chars))))))
+
+(define (only-files file)
+ (catch 'system-error
+ (lambda ()
+ (stat file))
+ (lambda args
+ (let ((errno (system-error-errno args)))
+ (format (current-error-port) "~a: ~a~%"
+ file (strerror errno))
+ #f))))
+
+(define (wc-print file)
+ (let-values (((lines chars)
+ (call-with-input-file file lines+chars)))
+ (format #t "~a ~a ~a~%" lines chars file)))
+
+(define (wc-l-print file)
+ (let-values (((lines chars)
+ (call-with-input-file file lines+chars)))
+ (format #t "~a ~a~%" lines file)))
+
+(define (wc-c-print file)
+ (let-values (((lines chars)
+ (call-with-input-file file lines+chars)))
+ (format #t "~a ~a~%" chars file)))
+
+(define (wc-command-implementation . files)
+ (for-each wc-print (filter only-files files)))
+
+(define (wc-l-command-implementation . files)
+ (for-each wc-l-print (filter only-files files)))
+
+(define (wc-c-command-implementation . files)
+ (for-each wc-c-print (filter only-files files)))
+
+(define (wc-commands . args)
+ (cond ((member "-l" args) `((@@ (guix build bournish)
wc-l-command-implementation) ,@(delete "-l" args)))
+ ((member "-c" args) `((@@ (guix build bournish)
wc-c-command-implementation) ,@(delete "-c" args)))
+ (else `((@@ (guix build bournish) wc-command-implementation) ,@args))))
+
(define (help-command . _)
(display "\
Hello, this is Bournish, a minimal Bourne-like shell in Guile!
@@ -129,7 +182,8 @@ commands such as 'ls' and 'cd'; it lacks globbing,
pipes---everything.\n"))
("help" ,help-command)
("ls" ,ls-command)
("which" ,which-command)
- ("cat" ,cat-command)))
+ ("cat" ,cat-command)
+ ("wc" ,wc-commands)))
(define (read-bournish port env)
"Read a Bournish expression from PORT, and return the corresponding Scheme
--
2.8.4
signature.asc
Description: PGP signature
