Add support for allowDashes

Add support for `allowDashes` as an option, next to
`allowApostrophes`, to control whether hyphens are normalised.

Closes GH-1.

Author: Dave Newton

index.js

@@ -20,7 +20,7 @@ var toString = require('nlcst-to-string');
  * Constants.
  */
 
-var ALL = /[-'’]/g;
+var ALL = /[-']/g;
 var DASH = /-/g;
 var APOSTROPHE = /’/g;
 var QUOTE = '\'';
@@ -30,18 +30,28 @@ var EMPTY = '';
  * Normalize `value`.
  *
  * @param {string} value - Value to normalize.
- * @param {boolean} allowApostrophes - Do not strip
- *   apostrophes.
+ * @param {Object?} options - Control stripping
+ *   apostrophes and dashes.
  * @return {string} - Normalized `value`.
  */
-function normalize(value, allowApostrophes) {
+function normalize(value, options) {
+    var settings = options || {};
+    var allowApostrophes = settings.allowApostrophes;
+    var allowDashes = settings.allowDashes;
     var result = (typeof value === 'string' ? value : toString(value))
-        .toLowerCase();
+        .toLowerCase()
+        .replace(APOSTROPHE, QUOTE);
+
+    if (allowApostrophes && allowDashes) {
+        return result;
+    }
 
     if (allowApostrophes) {
-        return result
-            .replace(APOSTROPHE, QUOTE)
-            .replace(DASH, EMPTY);
+        return result.replace(DASH, EMPTY);
+    }
+
+    if (allowDashes) {
+        return result.replace(QUOTE, EMPTY);
     }
 
     return result.replace(ALL, EMPTY);

readme.md

@@ -44,7 +44,7 @@ normalize({
 
 ## API
 
-### `normalize(value[, allowApostrophes])`
+### `normalize(value[, options])`
 
 Quote a value.
 
@@ -53,8 +53,13 @@ Quote a value.
 *   `value` ([`Node`][nlcst-node], `Array.<Node>`, or `string`)
     — Value to normalize;
 
-*   `allowApostrophes` (`boolean`, default: `false`)
-    — Do not strip apostrophes (but do normalize them).
+*   `options` (`Object?`):
+
+    *   `allowApostrophes` (`boolean`, default: `false`)
+        — Do not strip apostrophes (`'`);
+
+    *   `allowDashes` (`boolean`, default: `false`)
+        — Do not strip hyphens (`-`).
 
 **Returns**: `string` — Normalized value.