From f909c39530c727f414c8c827bdbccb2285ad1cc5 Mon Sep 17 00:00:00 2001
From: Efraim Flashner <address@hidden>
Date: Sun, 22 May 2016 14:56:06 +0300
Subject: [PATCH] Bournish: Add `wc' command.

* guix/build/bournish.scm (file-size, wc-c-command, wc-w-command,
wc-l-command, wc-command): New variables.
(%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 4022796..d133796 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 <address@hidden>
+;;; Copyright © 2016 Efraim Flashner <address@hidden>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -21,11 +22,13 @@
   #:use-module (system base compile)
   #:use-module (system repl command)
   #:use-module (system repl common)
+  ;#:use-module (ice-9 streams)
   #:use-module (ice-9 rdelim)
   #:use-module (ice-9 match)
   #:use-module (ice-9 ftw)
   #:use-module (srfi srfi-1)
   #:use-module (srfi srfi-26)
+  #:use-module (srfi srfi-41)
   #:export (%bournish-language))
 
 ;;; Commentary:
@@ -103,6 +106,56 @@ characters."
        ((@ (guix build utils) dump-port) port (current-output-port))
        *unspecified*)))
 
+(define (file-size file)
+    (stat:size (stat file)))
+
+(define (wc-c-command file)
+  ;; Faster when only `wc -c' is called
+  (file-size file))
+
+(define (wc-l-command file)
+  ;; Faster when only `wc -l' is called
+  (stream-length
+    (stream-filter
+      (lambda (chr)
+        (char=? chr #\newline))
+      (port->stream (open-file file "r")))))
+
+;(define (wc-l-command file)
+;  (call-with-input-file file
+;    (lambda (port)
+
+(define (lines+chars port)
+  ;; Return the number of lines and number of chars read from PORT.
+  (let loop ((lines 0) (words 0) (chars 0))
+    (match (read-char port)
+      ((? eof-object?)              ;done!
+       (values lines words chars))
+      (#\newline                    ;recurse
+       (loop (1+ lines) (1+ words) (1+ chars)))
+      ((and (char-set<= ? char-set:blank) ; need to fix/replace the '?'
+            (char-set<= (peek-char port) char-set:graphic))
+       (loop lines (1+ words) (1+ chars)))
+      (_                            ;recurse
+       (loop lines words (1+ chars))))))
+
+(define (wc-command file)
+  ((lambda (lines words chars) ; lambda doesn't like 3 variables
+     (format #t "~a ~a ~a ~a~%" lines words chars file))
+   (call-with-input-file file lines+chars)))
+
+;  let-values is undefined
+;  (let-values (((lines words chars)
+;    (call-with-input-file file lines+chars)))
+;      (format #t "~a ~a ~a ~a~%" lines chars words file)))
+
+;(define (wc-command file)
+;  (let ((wc-l (wc-l-command file))
+;        (wc-w (wc-w-command file))
+;        (wc-c (wc-c-command file)))
+;    (format #t "~{~a ~}\n"
+;            (list wc-l wc-w wc-c file))))
+
 (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-command)))
 
 (define (read-bournish port env)
   "Read a Bournish expression from PORT, and return the corresponding Scheme
-- 
2.8.3