s-chop-suffix

README.md

@@ -9,19 +9,33 @@ This is so much a work in progress that you should definitely not be using it ye
 ## Functions
 
 * [s-trim](#s-trim-s) `(s)`
+* [s-chop-suffix](#s-chop-suffix-suffix-s) `(suffix s)`
 
 ## Documentation and examples
 
 ### s-trim `(s)`
 
-Remove whitespace at beginning and end of string.
+Remove whitespace at beginning and end of `s`.
 
 ```cl
 (s-trim "trim ") ;; => "trim"
 (s-trim " this") ;; => "this"
 (s-trim " only  trims beg and end  ") ;; => "only  trims beg and end"
 ```
 
+### s-chop-suffix `(suffix s)`
+
+Remove `suffix` if it is at end of `s`.
+
+```cl
+(s-chop-suffix "-test.js" "penguin-test.js") ;; => "penguin"
+(s-chop-suffix "
+" "no newlines
+") ;; => "no newlines"
+(s-chop-suffix "
+" "no newlines") ;; => "no newlines"
+```
+
 
 ## Development
 

examples.el

@@ -8,5 +8,9 @@
 (defexamples s-trim
   (s-trim "trim ") => "trim"
   (s-trim " this") => "this"
-  (s-trim " only  trims beg and end  ") => "only  trims beg and end"
-)
+  (s-trim " only  trims beg and end  ") => "only  trims beg and end")
+
+(defexamples s-chop-suffix
+  (s-chop-suffix "-test.js" "penguin-test.js") => "penguin"
+  (s-chop-suffix "\n" "no newlines\n") => "no newlines"
+  (s-chop-suffix "\n" "no newlines") => "no newlines")

s.el

@@ -25,10 +25,18 @@
 ;;; Code:
 
 (defun s-trim (s)
-  "Remove whitespace at beginning and end of string."
+  "Remove whitespace at beginning and end of S."
   (if (string-match "\\`[ \t\n\r]+" s) (setq s (replace-match "" t t s)))
   (if (string-match "[ \t\n\r]+\\'" s) (setq s (replace-match "" t t s)))
   s)
 
+(defun s-chop-suffix (suffix s)
+  "Remove SUFFIX if it is at end of S."
+  (let ((pos (- (length suffix))))
+    (if (and (>= (length s) (length suffix))
+             (string= suffix (substring s pos)))
+        (substring s 0 pos)
+      s)))
+
 (provide 's)
 ;;; s.el ends here