Added OneOrMore AST node.

This speeds up the benchmark suite execution by 1.08% on V8.

Detailed results (benchmark suite totals):

---------------------------------
 Test #     Before       After
---------------------------------
      1   28.38 kB/s   28.72 kB/s
      2   28.52 kB/s   28.84 kB/s
      3   28.41 kB/s   28.83 kB/s
      4   28.47 kB/s   28.81 kB/s
      5   28.64 kB/s   28.76 kB/s
---------------------------------
Average   28.48 kB/s   28.79 kB/s
---------------------------------

Mozilla/5.0 (X11; U; Linux i686; en-US) AppleWebKit/533.2 (KHTML, like Gecko) Chrome/5.0.342.9 Safari/533.2

lib/compiler.js

@@ -200,6 +200,8 @@ PEG.Grammar.Choice = function(alternatives) {
 
 PEG.Grammar.ZeroOrMore = function(element) { this._element = element; };
 
+PEG.Grammar.OneOrMore = function(element) { this._element = element; };
+
 PEG.Grammar.NotPredicate = function(expression) {
   this._expression = expression;
 };
@@ -240,6 +242,9 @@ PEG.Grammar.extendNodes("checkReferencedRulesExist", {
   ZeroOrMore:
     function(grammar) { this._element.checkReferencedRulesExist(grammar); },
 
+  OneOrMore:
+    function(grammar) { this._element.checkReferencedRulesExist(grammar); },
+
   NotPredicate:
     function(grammar) { this._expression.checkReferencedRulesExist(grammar); },
 
@@ -288,6 +293,11 @@ PEG.Grammar.extendNodes("checkNoLeftRecursion", {
       this._element.checkNoLeftRecursion(grammar, appliedRules);
     },
 
+  OneOrMore:
+    function(grammar, appliedRules) {
+      this._element.checkNoLeftRecursion(grammar, appliedRules);
+    },
+
   NotPredicate:
     function(grammar, appliedRules) {
       this._expression.checkNoLeftRecursion(grammar, appliedRules);
@@ -858,6 +868,28 @@ PEG.Grammar.ZeroOrMore.prototype.compile = function(resultVar) {
   );
 };
 
+PEG.Grammar.OneOrMore.prototype.compile = function(resultVar) {
+  var elementResultVar = PEG.Compiler.generateUniqueIdentifier("result");
+
+  return PEG.Compiler.formatCode(
+    "${elementCode}",
+    "if (${elementResultVar} !== null) {",
+    "  var ${resultVar} = [];",
+    "  while (${elementResultVar} !== null) {",
+    "    ${resultVar}.push(${elementResultVar});",
+    "    ${elementCode}",
+    "  }",
+    "} else {",
+    "  var ${resultVar} = null;",
+    "}",
+    {
+      elementCode:      this._element.compile(elementResultVar),
+      elementResultVar: elementResultVar,
+      resultVar:        resultVar
+    }
+  );
+};
+
 PEG.Grammar.NotPredicate.prototype.compile = function(resultVar) {
   var savedPosVar                 = PEG.Compiler.generateUniqueIdentifier("savedPos");
   var savedReportMatchFailuresVar = PEG.Compiler.generateUniqueIdentifier("savedReportMatchFailuresVar");

lib/metagrammar.pegjs

@@ -40,12 +40,7 @@ suffixed
       return new PEG.Grammar.Choice([$1, new PEG.Grammar.Literal("")]);
     }
   / primary star { return new PEG.Grammar.ZeroOrMore($1); }
-  / primary plus {
-      return new PEG.Grammar.Action(
-        new PEG.Grammar.Sequence([$1, new PEG.Grammar.ZeroOrMore($1)]),
-        function(first, rest) { return [first].concat(rest); }
-      );
-    }
+  / primary plus { return new PEG.Grammar.OneOrMore($1);  }
   / primary
 
 primary

test/compiler-test.js

@@ -192,6 +192,7 @@ test("buildParser reports missing referenced rules", function() {
     'start: missing / "a" / "b"',
     'start: "a" / "b" / missing',
     'start: missing*',
+    'start: missing+',
     'start: !missing',
     'start: &missing',
     'start: missing { }'
@@ -214,6 +215,7 @@ test("buildParser reports left recursion", function() {
     'start: start / "a" / "b"',
     'start: "a" / "b" / start',
     'start: start*',
+    'start: start+',
     'start: !start',
     'start: &start',
     'start: start { }',

test/metagrammar-test.js

@@ -149,13 +149,7 @@ with (PEG.Grammar) {
   test("parses suffixed", function() {
     grammarParserParses('start: "abcd"?', oneRuleGrammar(choice));
     grammarParserParses('start: "abcd"*', oneRuleGrammar(new ZeroOrMore(literalAbcd)));
-    grammarParserParses(
-      'start: "abcd"+',
-      oneRuleGrammar(new Action(
-        new Sequence([literalAbcd, new ZeroOrMore(literalAbcd)]),
-        function(first, rest) { return [first].concat(rest); }
-      ))
-    );
+    grammarParserParses('start: "abcd"+', oneRuleGrammar(new OneOrMore(literalAbcd)));
     grammarParserParses('start: "abcd"', literalGrammar("abcd"));
   });