ADDED   graphspell-js/dic_merger.js
Index: graphspell-js/dic_merger.js
==================================================================
--- graphspell-js/dic_merger.js
+++ graphspell-js/dic_merger.js
@@ -0,0 +1,55 @@
+// Dictionaries merger
+
+"use strict";
+
+if (typeof(process) !== 'undefined') {
+    var dawg = require("./dawg.js");
+    var ibdawg = require("./ibdawg.js");
+}
+else if (typeof(require) !== 'undefined') {
+    var dawg = require("resource://grammalecte/graphspell/dawg.js");
+    var ibdawg = require("resource://grammalecte/graphspell/ibdawg.js");
+}
+
+
+const dic_merger = {
+
+    merge: function (lDict, cStemming, sLangCode, sLangName, sDicName, sDescription, xProgressBar=null) {
+        // merge a list of dictionaries (given as JSON objects)
+        // return a merged dictionary as JSON object.
+        if (xProgressBar) {
+            xProgressBar.max = lDict.length;
+            xProgressBar.value = 0;
+        }
+        let lEntry = [];
+        for (let oDict of lDict) {
+            // generate words list from selected dictionaries
+            if (xProgressBar) {
+                xProgressBar.value += 1;
+            }
+            try {
+                let oIBDAWG = new IBDAWG(oDict);
+                for (let aRes of oIBDAWG.select()) {
+                    lEntry.push(aRes);
+                }
+            }
+            catch (e) {
+                console.error(e);
+            }
+        }
+        if (xProgressBar) {
+            xProgressBar.value = xProgressBar.max;
+        }
+        try {
+            let oDAWG = new DAWG(lEntry, cStemming, sLangCode, sLangName, sDicName, sDescription, xProgressBar);
+            let oDict = oDAWG.createBinaryJSON(1);
+            return oDict;
+        }
+        catch (e) {
+            console.log("Dictionaries merger: unable to generate merged dictionary");
+            console.error(e);
+            return null;
+        }
+    }
+
+}