diff options
Diffstat (limited to 'src/clojure/contrib/str_utils2.clj')
| -rw-r--r-- | src/clojure/contrib/str_utils2.clj | 105 |
1 files changed, 90 insertions, 15 deletions
diff --git a/src/clojure/contrib/str_utils2.clj b/src/clojure/contrib/str_utils2.clj index 5a32df6f..9a1ea9f7 100644 --- a/src/clojure/contrib/str_utils2.clj +++ b/src/clojure/contrib/str_utils2.clj @@ -1,7 +1,7 @@ -;;; str_utils2.clj -- experimental new string utilities for Clojure +;;; str_utils2.clj -- functional string utilities for Clojure ;; by Stuart Sierra, http://stuartsierra.com/ -;; June 4, 2009 +;; August 19, 2009 ;; Copyright (c) Stuart Sierra, 2009. All rights reserved. The use ;; and distribution terms for this software are covered by the Eclipse @@ -29,8 +29,8 @@ Some ideas are borrowed from http://github.com/francoisdevlin/devlinsf-clojure-utils/"} clojure.contrib.str-utils2 - (:refer-clojure :exclude (take replace drop butlast partition contains? get)) - (:require [clojure.contrib.java-utils :as j]) + (:refer-clojure :exclude (take replace drop butlast partition + contains? get repeat reverse partial)) (:import (java.util.regex Pattern))) @@ -88,12 +88,13 @@ (lazy-seq (f s 0)))) (defn escape - "Escapes characters in string according to a cmap, a function or map - from characters to their replacements." + "Returns a new String by applying cmap (a function or a map) to each + character in s. If cmap returns nil, the original character is + added to the output unchanged." [#^String s cmap] (let [buffer (StringBuilder. (.length s))] (dochars [c s] - (if-let [r (cmap s)] + (if-let [r (cmap c)] (.append buffer r) (.append buffer c))) (.toString buffer))) @@ -104,7 +105,10 @@ (every? (fn [#^Character c] (Character/isWhitespace c)) s)) (defn take - "Take first n characters from s, up to the length of s." + "Take first n characters from s, up to the length of s. + + Note the argument order is the opposite of clojure.core/take; this + is to keep the string as the first argument for use with ->" [#^String s n] (if (< (count s) n) s @@ -112,14 +116,20 @@ (defn drop [#^String s n] "Drops first n characters from s. Returns an empty string if n is - greater than the length of s." + greater than the length of s. + + Note the argument order is the opposite of clojure.core/drop; this + is to keep the string as the first argument for use with ->" (if (< (count s) n) "" (.substring s n))) (defn butlast "Returns s without the last n characters. Returns an empty string - if n is greater than the length of s." + if n is greater than the length of s. + + Note the argument order is the opposite of clojure.core/butlast; + this is to keep the string as the first argument for use with ->" [#^String s n] (if (< (count s) n) "" @@ -132,6 +142,16 @@ s (.substring s (- (count s) n)))) +(defn repeat + "Returns a new String containing s repeated n times." + [#^String s n] + (apply str (clojure.core/repeat n s))) + +(defn reverse + "Returns s with its characters reversed." + [#^String s] + (.toString (.reverse (StringBuilder. s)))) + (defmulti #^{:doc "Replaces all instances of pattern in string with replacement. @@ -224,9 +244,13 @@ (apply str (interpose separator coll))) (defn chop - "Removes the last character of string." + "Removes the last character of string, does nothing on a zero-length + string." [#^String s] - (subs s 0 (dec (count s)))) + (let [size (count s)] + (if (zero? size) + s + (subs s 0 (dec (count s)))))) (defn chomp "Removes all trailing newline \\n or return \\r characters from @@ -235,10 +259,34 @@ (replace s #"[\r\n]+$" "")) (defn title-case [#^String s] - (throw (IllegalStateException. "title-case not implemented yet."))) + (throw (Exception. "title-case not implemeted yet"))) + +(defn swap-case + "Changes upper case characters to lower case and vice-versa. + Handles Unicode supplementary characters correctly. Uses the + locale-sensitive String.toUpperCase() and String.toLowerCase() + methods." + [#^String s] + (let [buffer (StringBuilder. (.length s)) + ;; array to make a String from one code point + #^"[I" array (make-array Integer/TYPE 1)] + (docodepoints [c s] + (aset-int array 0 c) + (if (Character/isLowerCase c) + ;; Character.toUpperCase is not locale-sensitive, but + ;; String.toUpperCase is; so we use a String. + (.append buffer (.toUpperCase (String. array 0 1))) + (.append buffer (.toLowerCase (String. array 0 1))))) + (.toString buffer))) -(defn swap-case [#^String s] - (throw (IllegalStateException. "swap-case not implemented yet."))) +(defn capitalize + "Converts first character of the string to upper-case, all other + characters to lower-case." + [#^String s] + (if (< (count s) 2) + (.toUpperCase s) + (str (.toUpperCase #^String (subs s 0 1)) + (.toLowerCase #^String (subs s 1))))) (defn ltrim "Removes whitespace from the left side of string." @@ -255,6 +303,33 @@ [#^String s] (seq (.split #"\r?\n" s))) +;; borrowed from compojure.str-utils, by James Reeves, EPL 1.0 +(defn map-str + "Apply f to each element of coll, concatenate all results into a + String." + [f coll] + (apply str (map f coll))) + +;; borrowed from compojure.str-utils, by James Reeves, EPL 1.0 +(defn grep + "Filters elements of coll by a regular expression. The String + representation (with str) of each element is tested with re-find." + [re coll] + (filter (fn [x] (re-find re (str x))) coll)) + +(defn partial + "Like clojure.core/partial for functions that take their primary + argument first. + + Takes a function f and its arguments, NOT INCLUDING the first + argument. Returns a new function whose first argument will be the + first argument to f. + + Example: (str-utils2/partial str-utils2/take 2) + ;;=> (fn [s] (str-utils2/take s 2))" + [f & args] + (fn [s & more] (apply f s (concat args more)))) + ;;; WRAPPERS |