Read available units/unit data structure

README.md

@@ -256,6 +256,25 @@ var qty = Qty('1.1234 m');
 qty.format(); // same units, current default formatter => '1.12 m'
 ```
 
+### Unit names
+
+Unit names can be extracted using `Qty#getUnits`, which returns an object with
+all available unit names, including prefixes, and their synonyms, categorized by
+kind. Can optionally be restricted to only one kind.
+
+```javascript
+var units = Qty.getUnits(); // dictionary containing all units, by category
+                            // { ...,
+                            // length: { m: ["m","meter","meters",
+                            //     "metre","metres"], ...},
+                            //  ... }
+
+var lengthUnits = Qty.getUnits("length"); // dictionary containing all length
+                                          // units
+                                          // { m: ["m","meter","meters","metre",
+                                          //     "metres"] }
+```
+
 ### Temperatures
 
 Like ruby-units, JS-quantities makes a distinction between a temperature (which

spec/quantitiesSpec.js

@@ -1154,4 +1154,24 @@ describe("js-quantities", function() {
     });
   });
 
+  describe("Qty.getUnits", function() {
+    it("should return a populated <string, Array<string>> dictionary of all unit names", function() {
+      var units = Qty.getUnits(),
+          expectedKey = "meter",
+          expectedValue = ["m","meter","meters","metre","metres"];
+
+      expect(units.length[expectedKey]).toEqual(expectedValue);
+    });
+
+    it ("should optionally restrict returned units to one kind", function() {
+      var resistanceUnits = Qty.getUnits("resistance"),
+          unexpectedKey = "meter",
+          expectedKey = "ohm",
+          expectedValue = ["Ohm", "ohm"];
+
+      expect(Object.keys(resistanceUnits).indexOf(unexpectedKey)).toBe(-1);
+      expect(resistanceUnits[expectedKey]).toEqual(expectedValue);
+    });
+  });
+
 });

src/quantities.js

@@ -452,6 +452,35 @@ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLI
     };
   };
 
+  /**
+   * Returns an object with the names of the available units, categorized by
+   * kind. Can optionally be restricted to only one kind.
+   *
+   * @param {string} kind optionally restrict to this kind
+   * @returns {Object<string, Array<string>} unit names
+   */
+  Qty.getUnits = function(kind) {
+    var kinds = {},
+        k;
+    for (var unitId in UNITS) {
+      k = UNITS[unitId][2];
+      if (k.length === 0) {
+        continue;
+      }
+      if (kinds[k] === undefined) {
+        kinds[k] = {};
+      }
+      kinds[k][unitId.substr(1, unitId.length - 2)] = UNITS[unitId][0];
+    }
+    if (kind) {
+      if (kinds[kind] === undefined) {
+        throw new QtyError(kind + ": Kind not recognized.");
+      }
+      return kinds[kind];
+    }
+    return kinds;
+  };
+
   /**
    * Default formatter
    *