diff --git a/guix/utils.scm b/guix/utils.scm index 3cbed2fd0f..0b09affffd 100644 --- a/guix/utils.scm +++ b/guix/utils.scm @@ -60,6 +60,7 @@ version-compare version>? package-name->name+version + string-tokenize* file-extension call-with-temporary-output-file fold2)) @@ -471,6 +472,33 @@ introduce the version part." (let ((dot (string-rindex file #\.))) (and dot (substring file (+ 1 dot) (string-length file))))) +(define (string-tokenize* string separator) + "Return the list of substrings of STRING separated by SEPARATOR. This is +like `string-tokenize', but SEPARATOR is a string." + (define (index string what) + (let loop ((string string) + (offset 0)) + (cond ((string-null? string) + #f) + ((string-prefix? what string) + offset) + (else + (loop (string-drop string 1) (+ 1 offset)))))) + + (define len + (string-length separator)) + + (let loop ((string string) + (result '())) + (cond ((index string separator) + => + (lambda (offset) + (loop (string-drop string (+ offset len)) + (cons (substring string 0 offset) + result)))) + (else + (reverse (cons string result)))))) + (define (call-with-temporary-output-file proc) "Call PROC with a name of a temporary file and open output port to that file; close the file and delete it when leaving the dynamic extent of this diff --git a/tests/utils.scm b/tests/utils.scm index fa7d7b03fd..97547a6d62 100644 --- a/tests/utils.scm +++ b/tests/utils.scm @@ -64,6 +64,16 @@ ("nixpkgs" "1.0pre22125_a28fe19") ("gtk2" "2.38.0")))) +(test-equal "string-tokenize*" + '(("foo") + ("foo" "bar" "baz") + ("foo" "bar" "") + ("foo" "bar" "baz")) + (list (string-tokenize* "foo" ":") + (string-tokenize* "foo;bar;baz" ";") + (string-tokenize* "foo!bar!" "!") + (string-tokenize* "foo+-+bar+-+baz" "+-+"))) + (test-equal "fold2, 1 list" (list (reverse (iota 5)) (map - (reverse (iota 5))))