summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorIan Price <ianprice90@googlemail.com>2012-11-22 09:45:12 +0000
committerLudovic Courtès <ludo@gnu.org>2012-11-22 22:26:16 +0100
commit06906f370f77cbab520ff0d3c47449526934a9c8 (patch)
tree756fa6471d541b7c115227028e2674d9fe209322
parent2c7b7e0f214be5ec5184949a94209668775f60bc (diff)
downloadguile-06906f370f77cbab520ff0d3c47449526934a9c8.tar.gz
R6RS `string-for-each' should accept multiple string arguments
* module/rnrs/base.scm (string-for-each): Rewrite. * test-suite/tests/r6rs-base.test ("string-for-each"): Add tests.
-rw-r--r--module/rnrs/base.scm39
-rw-r--r--test-suite/tests/r6rs-base.test40
2 files changed, 78 insertions, 1 deletions
diff --git a/module/rnrs/base.scm b/module/rnrs/base.scm
index 499a22444..9fedac01d 100644
--- a/module/rnrs/base.scm
+++ b/module/rnrs/base.scm
@@ -73,7 +73,7 @@
let-syntax letrec-syntax
syntax-rules identifier-syntax)
- (import (rename (except (guile) error raise map)
+ (import (rename (except (guile) error raise map string-for-each)
(log log-internal)
(euclidean-quotient div)
(euclidean-remainder mod)
@@ -86,6 +86,43 @@
(inexact->exact exact))
(srfi srfi-11))
+ (define string-for-each
+ (case-lambda
+ ((proc string)
+ (let ((end (string-length string)))
+ (let loop ((i 0))
+ (unless (= i end)
+ (proc (string-ref string i))
+ (loop (+ i 1))))))
+ ((proc string1 string2)
+ (let ((end1 (string-length string1))
+ (end2 (string-length string2)))
+ (unless (= end1 end2)
+ (assertion-violation 'string-for-each
+ "string arguments must all have the same length"
+ string1 string2))
+ (let loop ((i 0))
+ (unless (= i end1)
+ (proc (string-ref string1 i)
+ (string-ref string2 i))
+ (loop (+ i 1))))))
+ ((proc string . strings)
+ (let ((end (string-length string))
+ (ends (map string-length strings)))
+ (for-each (lambda (x)
+ (unless (= end x)
+ (apply assertion-violation
+ 'string-for-each
+ "string arguments must all have the same length"
+ string strings)))
+ ends)
+ (let loop ((i 0))
+ (unless (= i end)
+ (apply proc
+ (string-ref string i)
+ (map (lambda (s) (string-ref s i)) strings))
+ (loop (+ i 1))))))))
+
(define map
(case-lambda
((f l)
diff --git a/test-suite/tests/r6rs-base.test b/test-suite/tests/r6rs-base.test
index df11d67b3..fb491419a 100644
--- a/test-suite/tests/r6rs-base.test
+++ b/test-suite/tests/r6rs-base.test
@@ -196,3 +196,43 @@
(guard (condition ((assertion-violation? condition) #t))
(assert #f)
#f)))
+
+(with-test-prefix "string-for-each"
+ (pass-if "reverse string"
+ (let ((s "reverse me") (l '()))
+ (string-for-each (lambda (x) (set! l (cons x l))) s)
+ (equal? "em esrever" (list->string l))))
+ (pass-if "two strings good"
+ (let ((s1 "two legs good")
+ (s2 "four legs bad")
+ (c '()))
+ (string-for-each (lambda (c1 c2)
+ (set! c (cons* c2 c1 c)))
+ s1 s2)
+ (equal? (list->string c)
+ "ddaobo gs gsegle lr uoowft")))
+ (pass-if "two strings bad"
+ (let ((s1 "frotz")
+ (s2 "veeblefetzer"))
+ (guard (condition ((assertion-violation? condition) #t))
+ (string-for-each (lambda (s1 s2) #f) s1 s2)
+ #f)))
+ (pass-if "many strings good"
+ (let ((s1 "foo")
+ (s2 "bar")
+ (s3 "baz")
+ (s4 "zot")
+ (c '()))
+ (string-for-each (lambda (c1 c2 c3 c4)
+ (set! c (cons* c4 c3 c2 c1 c)))
+ s1 s2 s3 s4)
+ (equal? (list->string c)
+ "tzrooaaozbbf")))
+ (pass-if "many strings bad"
+ (let ((s1 "foo")
+ (s2 "bar")
+ (s3 "baz")
+ (s4 "quux"))
+ (guard (condition ((assertion-violation? condition) #t))
+ (string-for-each (lambda _ #f) s1 s2 s3 s4)
+ #f))))