Added a simple unlexer in the JavaScript library.

lib/javascript/gflib.js

@@ -52,33 +52,48 @@ Fun.prototype.isComplete = function() {
 /* Concrete syntax terms */
 
 function Arr() { this.arr = copy_arguments(arguments, 0); }
-Arr.prototype.print = function() { return this.arr[0].print(); };
+Arr.prototype.tokens = function() { return this.arr[0].tokens(); };
 Arr.prototype.sel = function(i) { return this.arr[i.toIndex()]; };
 
 function Seq() { this.seq = copy_arguments(arguments, 0); }
-Seq.prototype.print = function() { return join_print(this.seq, " "); };
+Seq.prototype.tokens = function() { 
+	var xs = new Array();
+	for (var i in this.seq) {
+		var ys = this.seq[i].tokens();
+		for (var j in ys) {
+			xs.push(ys[j]);
+		}		
+	}
+	return xs; 
+};
 
 function Variants() { this.variants = copy_arguments(arguments, 0); }
-Variants.prototype.print = function() { return this.variants[0].print(); };
+Variants.prototype.tokens = function() { return this.variants[0].tokens(); };
 
 function Rp(index,value) { this.index = index; this.value = value; }
-Rp.prototype.print = function() { return this.index; };
+Rp.prototype.tokens = function() { return new Array(this.index); };
 Rp.prototype.toIndex = function() { return this.index.toIndex(); };
 
 function Suffix(prefix,suffix) { this.prefix = prefix; this.suffix = suffix; };
-Suffix.prototype.print = function() { return this.prefix + this.suffix.print(); };
+Suffix.prototype.tokens = function() {
+	var xs = this.suffix.tokens();
+	for (var i in xs) {
+		xs[i] = this.prefix + xs[i];
+	}
+	return xs;
+};
 Suffix.prototype.sel = function(i) { return new Suffix(this.prefix, this.suffix.sel(i)); };
 
 function Meta() { }
-Meta.prototype.print = function() { return "?"; };
+Meta.prototype.tokens = function() { return new Array("?"); };
 Meta.prototype.toIndex = function() { return 0; };
 Meta.prototype.sel = function(i) { return this; };
 
 function Str(value) { this.value = value; }
-Str.prototype.print = function() { return this.value; };
+Str.prototype.tokens = function() { return new Array(this.value); };
 
 function Int(value) { this.value = value; }
-Int.prototype.print = function() { return this.value.toString(); };
+Int.prototype.tokens = function() { return new Array(this.value.toString()); };
 Int.prototype.toIndex = function() { return this.value; };
 
 /* Type annotation */
@@ -152,7 +167,9 @@ function Concrete(abstr) {
 Concrete.prototype.rule = function (name, cs) { return this.rules[name](cs); };
 Concrete.prototype.addRule = function (name, f) { this.rules[name] = f; };
 Concrete.prototype.lindef = function (cat, v) { return this.rules["_d"+cat]([new Str(v)]); } ;
-Concrete.prototype.linearize = function (tree) { return this.linearizeToTerm(tree).print(); };
+Concrete.prototype.linearize = function (tree) { 
+	return this.unlex(this.linearizeToTerm(tree).tokens());
+};
 Concrete.prototype.linearizeToTerm = function (tree) {
 	if (tree.isMeta()) {
 		if (isUndefined(tree.type)) {
@@ -168,6 +185,27 @@ Concrete.prototype.linearizeToTerm = function (tree) {
 		return this.rule(tree.name, cs);
 	}
 };
+Concrete.prototype.unlex = function (ts) {
+	if (ts.length == 0) {
+		return "";
+	}
+
+	var noSpaceAfter = /^[\(\-\[]/;
+	var noSpaceBefore = /^[\.\,\?\!\)\:\;\-\]]/;
+
+	var s = "";
+	for (var i = 0; i < ts.length; i++) {
+		var t = ts[i];
+		var after = i < ts.length-1 ? ts[i+1] : null;
+		s += t;
+		if (after != null && !t.match(noSpaceAfter) 
+				  && !after.match(noSpaceBefore)) {
+			s += " ";
+		}
+	}
+	return s;
+};
+
 
 /* Utilities */
 
@@ -212,16 +250,3 @@ function copy_arguments(args, start) {
 	}
 	return arr;
 }
-
-function join_print(values, glue) {
-	var str = "";
-	for (var i in values) {
-		var s = values[i].print();
-		if (s.length > 0) {
-			if (str.length > 0) { str += glue; }
-			str += s;
-		}
-	}
-	return str;
-}
-