Unfinished.

bottomUp/Parser.js

@@ -41,11 +41,11 @@
 			var left  = this.token.left,
 				right = this.stack.length ? this.stack[this.stack.length - 1].right : 0;
 
-			if(left > right){
+			if(right < left){
 				this.expected = this.token.next;
 				this.stack.push(this.token);
 				this.state = "supply";
-			}else if(left < right){
+			}else if(right > left){
 				this.state = this.stack.length ? "consume" : "eos";
 			}else{
 				if(this.stack.length){

bottomUp/Parser2.js

@@ -0,0 +1,82 @@
+/* UMD.define */ (typeof define=="function"&&define||function(d,f,m){m={module:module,require:require};module.exports=f.apply(null,d.map(function(n){return m[n]||require(n)}))})
+([], function(){
+	"use strict";
+
+	var consumeReadyState = {consume: 1, eos: 1},
+		eoi = {id: "End of Input", left: -1, right: -1};
+
+	function Parser2(grammar, name, priority){
+		this.reset(grammar, name, priority);
+	}
+
+	Parser2.prototype = {
+		reset: function(grammar, name, priority){
+			this.stack    = [];
+			this.state    = "supply";
+			this.grammar  = grammar;
+			this.expected = name || "main";
+			this.priority = priority || 0;
+		},
+		_consume: function(){
+			if(this.state == "eos"){
+				this.state = "done";
+				return this.token;
+			}
+			//assert((this.state in consumeReadyState) && this.stack.length);
+			var token = this.stack.pop();
+			this._decide();
+			return token;
+		},
+		_decide: function(token){
+			if(token){
+				//assert(this.state == "supply");
+				this.token = token;
+			}
+
+			var left  = this.token.left,
+				right = this.stack.length ? this.stack[this.stack.length - 1].right : this.priority;
+
+			if(right < left){
+				this.expected = this.token.next;
+				this.stack.push(this.token);
+				this.state = "supply";
+			}else{
+				this.state = this.stack.length ? "consume" : "eos";
+			}
+		},
+		getExpectedState: function(){
+			return this.state == "done" ? null : this.grammar[this.expected];
+		},
+		putToken: function(token, scanner){
+			if(token){
+				if(!token.ignore){
+					//assert(this.state == "supply");
+					this._decide(token);
+					while(this.state in consumeReadyState){
+						token = this._consume();
+						if(token !== eoi){
+							this.onToken(token);
+						}
+					}
+				}
+			}else{
+				this.putToken(eoi, scanner);
+				if(this.state != "done"){
+					throw Error("Can't find a legal token" +
+						(scanner ? " at (" + scanner.line + ", " + scanner.pos + ") in: " +
+							(scanner.buffer.length > 16 ? scanner.buffer.substring(0, 16) + "..." :
+								scanner.buffer) + "\n" : ".\n") +
+						"Tried '" + this.expected + "': " +
+						this.grammar[this.expected].tokens.map(function(token){
+							return "'" + token.id + "'";
+						}).join(", ") + ".");
+				}
+			}
+		},
+		onToken: function(token){
+			console.log(token.id + " (" + token.line + ", " + token.pos + "): " + token.value);
+		}
+	};
+
+	return Parser2;
+});

tests/expr2.js

@@ -0,0 +1,109 @@
+/* UMD.define */ (typeof define=="function"&&define||function(d,f,m){m={module:module,require:require};module.exports=f.apply(null,d.map(function(n){return m[n]||require(n)}))})
+(["../bottomUp/Grammar"], function(Grammar){
+	"use strict";
+
+	function operand(pattern){
+		return {
+			pattern: pattern,
+			left:    0,
+			right:   0,
+			next:    "operator"
+		};
+	}
+
+	function prefix(priority, pattern){
+		return {
+			pattern: pattern,
+			left:    priority || 70,
+			right:   0,
+			next:    "operator"
+		};
+	}
+
+	function infix(priority, pattern){
+		return {
+			pattern: pattern,
+			left:    priority,
+			right:   priority,
+			next:    "operand"
+		};
+	}
+
+	function infixr(priority, pattern){
+		return {
+			pattern: pattern,
+			left:    priority,
+			right:   priority - 1,
+			next:    "operand"
+		};
+	}
+
+	function pattern(priority, rule, next){
+		return {
+			pattern: rule[0],
+			left:    priority,
+			right:   0,
+			rule:    rule,
+			next:    next || "operator"
+		};
+	}
+
+	function maybe(){
+		var rule = Array.prototype.slice.call(arguments, 0);
+		rule.optional = true;
+		return rule;
+	}
+
+	function repeat(){
+		var rule = Array.prototype.slice.call(arguments, 0);
+		rule.optional = true;
+		rule.repeatable = true;
+		return rule;
+	}
+
+	var expr = new Grammar({
+			operand: {
+				// values
+				id:     operand(/[A-Za-z_\$]\w*/),
+				num:    operand(/(?:0|[1-9]\d*)(?:\.\d*)?(?:[eE][+-]?\d+)?|\.\d+(?:[eE][+-]?\d+)?/),
+				// unary prefix operators
+				"pre+": operand("+"),
+				"pre-": operand("-"),
+				// parentheses
+				"(":    operand(),
+				"[":    operand(),
+				// technical
+				ws: {
+					pattern: /[\u0009\u000B\u000C\u0020\u00A0\uFEFF]+/,
+					ignore:  true
+				},
+				crlf: {
+					pattern: /[\u000A\u2028\u2029]|\u000D\u000A|\u000D/,
+					ignore:  true
+				}
+			},
+			operator: {
+				// the ternary operator
+				"?": pattern(20, ["?", 0, ":", 0]),
+				// binary operators
+				"*": infix(60),
+				"/": infix(60),
+				"+": infix(50),
+				"-": infix(50),
+				// parentheses
+				sub:  pattern(80, ["[", 0, "]"]),
+				call: pattern(80, ["(", maybe(0, repeat(",", 0)), ")"]),
+				// technical
+				ws: {
+					pattern: /[\u0009\u000B\u000C\u0020\u00A0\uFEFF]+/,
+					ignore:  true
+				},
+				crlf: {
+					pattern: /[\u000A\u2028\u2029]|\u000D\u000A|\u000D/,
+					ignore:  true
+				}
+			}
+		});
+
+	return expr;
+});

tests/test_expr2.js

@@ -0,0 +1,33 @@
+var Scanner  = require("../Scanner");
+var Parser   = require("../bottomUp/Parser2");
+
+var expr = require("./expr2");
+
+
+var scanner = new Scanner();
+
+//scanner.addBuffer("(1 + 2) * 3[4]", true);
+scanner.addBuffer("[a[b]]", true);
+
+
+console.log("Buffer: " + scanner.buffer);
+
+var parser = new Parser(expr, "operand");
+
+for(;;){
+	var expected = parser.getExpectedState();
+	if(!expected){
+		// we are done
+		break;
+	}
+	var token = scanner.getToken(expected);
+	if(token === true){
+		throw Error("Scanner requests more data, which is impossible.");
+	}
+	parser.putToken(token, scanner);
+}
+
+if(!scanner.isFinished()){
+	throw Error("Unprocessed symbols: " +
+		(scanner.buffer.length > 16 ? scanner.buffer.substring(0, 16) + "..." : scanner.buffer));
+}

topDown/Grammar.js

@@ -29,7 +29,7 @@
 				}
 			});
 		}, this);
-	};
+	}
 
 	// helpers
 
@@ -133,7 +133,7 @@
 			makeState(item);
 			item = item.state;
 		}
-		if(!naked){
+		if(!naked && typeof item == "object"){
 			var newIndex = index + 1;
 			if(newIndex === rule.length && rule.repeatable){
 				newIndex = 0;