diff --git a/spec/behavior/generated-parser-behavior.spec.js b/spec/behavior/generated-parser-behavior.spec.js
index 8d8c90b..d72c23a 100644
--- a/spec/behavior/generated-parser-behavior.spec.js
+++ b/spec/behavior/generated-parser-behavior.spec.js
@@ -122,7 +122,7 @@ describe("generated parser behavior", function() {
   });
 
   varyOptimizationOptions(function(options) {
-    describe("initializer code", function() {
+    describe("initializer", function() {
       it("runs before the parsing begins", function() {
         var parser = PEG.buildParser([
               '{ var result = 42; }',
@@ -178,7 +178,22 @@ describe("generated parser behavior", function() {
       });
     });
 
-    describe("rule matching", function() {
+    describe("named rule", function() {
+      var parser = PEG.buildParser('start "start" = "a"');
+
+      it("delegates to the expression", function() {
+        expect(parser).toParse("a", "a");
+        expect(parser).toFailToParse("b");
+      });
+
+      it("overwrites expected string on failure", function() {
+        expect(parser).toFailToParse("b", {
+          expected: [{ type: "other", description: "start" }]
+        });
+      });
+    });
+
+    describe("rule", function() {
       var grammar = [
             '{ var n = 0; }',
             'start = (a "b") / (a "c") { return n; }',
@@ -200,238 +215,156 @@ describe("generated parser behavior", function() {
       }
     });
 
-    describe("named matching", function() {
-      var parser = PEG.buildParser('start "start" = "a"');
-
-      it("delegates to the expression", function() {
-        expect(parser).toParse("a", "a");
-        expect(parser).toFailToParse("b");
-      });
+    describe("literal", function() {
+      it("matches empty literal correctly", function() {
+        var parser = PEG.buildParser('start = ""', options);
 
-      it("overwrites expected string on failure", function() {
-        expect(parser).toFailToParse("b", {
-          expected: [{ type: "other", description: "start" }]
-        });
+        expect(parser).toParse("", "");
       });
-    });
 
-    describe("choice matching", function() {
-      it("matches correctly", function() {
-        var parser = PEG.buildParser('start = "a" / "b" / "c"', options);
+      it("matches one-character literal correctly", function() {
+        var parser = PEG.buildParser('start = "a"', options);
 
         expect(parser).toParse("a", "a");
-        expect(parser).toParse("b", "b");
-        expect(parser).toParse("c", "c");
-        expect(parser).toFailToParse("d");
-      });
-    });
-
-    describe("action code", function() {
-      it("tranforms the expression result by returnung a value", function() {
-        var parser = PEG.buildParser('start = "a" { return 42; }', options);
-
-        expect(parser).toParse("a", 42);
+        expect(parser).toFailToParse("b");
       });
 
-      it("is not called when the expression does not match", function() {
-        var parser = PEG.buildParser(
-              'start = "a" { throw "Boom!"; } / "b"',
-              options
-            );
+      it("matches multi-character literal correctly", function() {
+        var parser = PEG.buildParser('start = "abcd"', options);
 
-        expect(parser).toParse("b", "b");
+        expect(parser).toParse("abcd", "abcd");
+        expect(parser).toFailToParse("ebcd");
+        expect(parser).toFailToParse("afcd");
+        expect(parser).toFailToParse("abgd");
+        expect(parser).toFailToParse("abch");
       });
 
-      it("can use label variables", function() {
-        var parser = PEG.buildParser('start = a:"a" { return a; }', options);
+      it("is case sensitive without the \"i\" flag", function() {
+        var parser = PEG.buildParser('start = "a"', options);
 
         expect(parser).toParse("a", "a");
+        expect(parser).toFailToParse("A");
       });
 
-      it("can use the |text| function to get the text matched by the expression", function() {
-        var parser = PEG.buildParser(
-              'start = "a" "b" "c" { return text(); }',
-              options
-            );
-
-        expect(parser).toParse("abc", "abc");
-      });
-
-      it("can use the |offset| function to get the current parse position", function() {
-        var parser = PEG.buildParser(
-              'start = "a" ("b" { return offset(); })',
-              options
-            );
-
-        expect(parser).toParse("ab", ["a", 1]);
-      });
-
-      it("can use the |line| and |column| functions to get the current line and column", function() {
-        var parser = PEG.buildParser([
-              '{ var result; }',
-              'start  = line (nl+ line)* { return result; }',
-              'line   = thing (" "+ thing)*',
-              'thing  = digit / mark',
-              'digit  = [0-9]',
-              'mark   = "x" { result = [line(), column()]; }',
-              'nl     = ("\\r" / "\\n" / "\\u2028" / "\\u2029")'
-            ].join("\n"), options);
-
-        expect(parser).toParse("1\n2\n\n3\n\n\n4 5 x", [7, 5]);
-
-        /* Non-Unix newlines */
-        expect(parser).toParse("1\rx",   [2, 1]);   // Old Mac
-        expect(parser).toParse("1\r\nx", [2, 1]);   // Windows
-        expect(parser).toParse("1\n\rx", [3, 1]);   // mismatched
+      it("is case insensitive with the \"i\" flag", function() {
+        var parser = PEG.buildParser('start = "a"i', options);
 
-        /* Strange newlines */
-        expect(parser).toParse("1\u2028x", [2, 1]);   // line separator
-        expect(parser).toParse("1\u2029x", [2, 1]);   // paragraph separator
+        expect(parser).toParse("a", "a");
+        expect(parser).toParse("A", "A");
       });
 
-      it("can use variables defined in the initializer", function() {
-        var parser = PEG.buildParser([
-              '{ var v = 42 }',
-              'start = "a" { return v; }'
-            ].join("\n"), options);
+      it("advances position on success", function() {
+        var parser = PEG.buildParser('start = "a" .', options);
 
-        expect(parser).toParse("a", 42);
+        expect(parser).toParse("ab", ["a", "b"]);
       });
 
-      it("can use the |expected| function to trigger an error", function() {
-        var parser = PEG.buildParser(
-              'start = "a" { expected("a"); }',
-              options
-            );
+      it("sets expectation correctly on failure", function() {
+        var parser = PEG.buildParser('start = "a"', options);
 
-        expect(parser).toFailToParse("a", {
-          message:  'Expected a but "a" found.',
-          expected: [{ type: "other", description: "a" }],
-          found:    "a",
-          offset:   0,
-          line:     1,
-          column:   1
+        expect(parser).toFailToParse("b", {
+          expected: [{ type: "literal", value: "a", description: '"a"' }]
         });
       });
+    });
 
-      it("can use the |error| function to trigger an error", function() {
-        var parser = PEG.buildParser(
-              'start = "a" { error("a"); }',
-              options
-            );
+    describe("character class", function() {
+      it("matches empty class correctly", function() {
+        var parser = PEG.buildParser('start = []', options);
 
-        expect(parser).toFailToParse("a", {
-          message:  "a",
-          expected: null,
-          found:    "a",
-          offset:   0,
-          line:     1,
-          column:   1
-        });
+        expect(parser).toFailToParse("a");
       });
 
-      it("can use functions defined in the initializer", function() {
-        var parser = PEG.buildParser([
-              '{ function f() { return 42; } }',
-              'start = "a" { return f(); }'
-            ].join("\n"), options);
+      it("matches class with a character list correctly", function() {
+        var parser = PEG.buildParser('start = [abc]', options);
 
-        expect(parser).toParse("a", 42);
+        expect(parser).toParse("a", "a");
+        expect(parser).toParse("b", "b");
+        expect(parser).toParse("c", "c");
+        expect(parser).toFailToParse("d");
       });
 
-      it("can use the |parser| variable to access the parser object", function() {
-        var parser = PEG.buildParser(
-              'start = "a" { return parser; }',
-              options
-            );
+      it("matches class with a range correctly", function() {
+        var parser = PEG.buildParser('start = [a-c]', options);
 
-        expect(parser).toParse("a", parser);
+        expect(parser).toParse("a", "a");
+        expect(parser).toParse("b", "b");
+        expect(parser).toParse("c", "c");
+        expect(parser).toFailToParse("d");
       });
 
-      it("can use options passed to the parser", function() {
-        var parser = PEG.buildParser(
-              'start = "a" { return options; }',
-              options
-            );
+      it("matches inverted class correctly", function() {
+        var parser = PEG.buildParser('start = [^a]', options);
 
-        expect(parser).toParse("a", { a: 42 }, { a: 42 });
+        expect(parser).toFailToParse("a");
+        expect(parser).toParse("b", "b");
       });
-    });
 
-    describe("sequence matching", function() {
-      it("matches correctly", function() {
-        var parser = PEG.buildParser('start = "a" "b" "c"', options);
+      it("is case sensitive without the \"i\" flag", function() {
+        var parser = PEG.buildParser('start = [a]', options);
 
-        expect(parser).toParse("abc", ["a", "b", "c"]);
+        expect(parser).toParse("a", "a");
+        expect(parser).toFailToParse("A");
       });
 
-      it("does not advance position on failure", function() {
-        var parser = PEG.buildParser('start = "a" "b" / "a"', options);
+      it("is case insensitive with the \"i\" flag", function() {
+        var parser = PEG.buildParser('start = [a]i', options);
 
         expect(parser).toParse("a", "a");
+        expect(parser).toParse("A", "A");
       });
-    });
 
-    describe("labeled matching", function() {
-      it("delegates to the expression", function() {
-        var parser = PEG.buildParser('start = a:"a"', options);
+      it("advances position on success", function() {
+        var parser = PEG.buildParser('start = [a] .', options);
 
-        expect(parser).toParse("a", "a");
-        expect(parser).toFailToParse("b");
+        expect(parser).toParse("ab", ["a", "b"]);
       });
-    });
 
-    describe("text matching", function() {
-      it("matches correctly", function() {
-        var parser = PEG.buildParser('start = $("a" "b" "c")', options);
+      it("sets expectation correctly on failure", function() {
+        var parser = PEG.buildParser('start = [a]', options);
 
-        expect(parser).toParse("abc", "abc");
+        expect(parser).toFailToParse("b", {
+          expected: [{ type: "class", value: "[a]", description: "[a]" }]
+        });
       });
     });
 
-    describe("simple and matching", function() {
+    describe("dot", function() {
       it("matches correctly", function() {
-        var parser = PEG.buildParser('start = &"a" "a"', options);
+        var parser = PEG.buildParser('start = .', options);
 
-        expect(parser).toParse("a", [undefined, "a"]);
-        expect(parser).toFailToParse("b");
+        expect(parser).toParse("a", "a");
       });
 
-      it("does not advance position on success", function() {
-        var parser = PEG.buildParser('start = &"a" "a"', options);
+      it("advances position on success", function() {
+        var parser = PEG.buildParser('start = . .', options);
 
-        expect(parser).toParse("a", [undefined, "a"]);
+        expect(parser).toParse("ab", ["a", "b"]);
       });
 
-      it("does not influence expected strings on failure", function() {
-        var parser = PEG.buildParser('start = &"a"', options);
+      it("sets expectation correctly on failure", function() {
+        var parser = PEG.buildParser('start = .', options);
 
-        expect(parser).toFailToParse("b", { expected: [] });
+        expect(parser).toFailToParse("", {
+          expected: [{ type: "any", description: "any character" }]
+        });
       });
     });
 
-    describe("simple not matching", function() {
-      it("matches correctly", function() {
-        var parser = PEG.buildParser('start = !"a" "b"', options);
-
-        expect(parser).toParse("b", [undefined, "b"]);
-        expect(parser).toFailToParse("a");
-      });
-
-      it("does not advance position on failure", function() {
-        var parser = PEG.buildParser('start = !"a" / "a"', options);
-
-        expect(parser).toParse("a", "a");
-      });
-
-      it("does not influence expected strings on failure", function() {
-        var parser = PEG.buildParser('start = !"a"', options);
+    describe("rule reference", function() {
+      it("follows rule references", function() {
+        var parser = PEG.buildParser([
+              'start   = static / dynamic',
+              'static  = "C" / "C++" / "Java" / "C#"',
+              'dynamic = "Ruby" / "Python" / "JavaScript"'
+            ].join("\n"), options);
 
-        expect(parser).toFailToParse("a", { expected: [] });
+        expect(parser).toParse("Java",   "Java");
+        expect(parser).toParse("Python", "Python");
       });
     });
 
-    describe("semantic and code", function() {
+    describe("positive semantic predicate", function() {
       it("causes successful match by returning |true|", function() {
         var parser = PEG.buildParser('start = &{ return true; }', options);
 
@@ -531,7 +464,7 @@ describe("generated parser behavior", function() {
       });
     });
 
-    describe("semantic not code", function() {
+    describe("negative semantic predicate", function() {
       it("causes successful match by returning |false|", function() {
         var parser = PEG.buildParser('start = !{ return false; }', options);
 
@@ -631,7 +564,7 @@ describe("generated parser behavior", function() {
       });
     });
 
-    describe("optional matching", function() {
+    describe("optional", function() {
       it("matches correctly", function() {
         var parser = PEG.buildParser('start = "a"?', options);
 
@@ -640,7 +573,7 @@ describe("generated parser behavior", function() {
       });
     });
 
-    describe("zero or more matching", function() {
+    describe("zero or more", function() {
       it("matches correctly", function() {
         var parser = PEG.buildParser('start = "a"*', options);
 
@@ -650,7 +583,7 @@ describe("generated parser behavior", function() {
       });
     });
 
-    describe("one or more matching", function() {
+    describe("one or more", function() {
       it("matches correctly", function() {
         var parser = PEG.buildParser('start = "a"+', options);
 
@@ -660,153 +593,220 @@ describe("generated parser behavior", function() {
       });
     });
 
-    describe("rule reference matching", function() {
-      it("follows rule references", function() {
-        var parser = PEG.buildParser([
-              'start   = static / dynamic',
-              'static  = "C" / "C++" / "Java" / "C#"',
-              'dynamic = "Ruby" / "Python" / "JavaScript"'
-            ].join("\n"), options);
+    describe("text", function() {
+      it("matches correctly", function() {
+        var parser = PEG.buildParser('start = $("a" "b" "c")', options);
 
-        expect(parser).toParse("Java",   "Java");
-        expect(parser).toParse("Python", "Python");
+        expect(parser).toParse("abc", "abc");
       });
     });
 
-    describe("literal matching", function() {
-      it("matches empty literal correctly", function() {
-        var parser = PEG.buildParser('start = ""', options);
+    describe("positive simple predicate", function() {
+      it("matches correctly", function() {
+        var parser = PEG.buildParser('start = &"a" "a"', options);
 
-        expect(parser).toParse("", "");
+        expect(parser).toParse("a", [undefined, "a"]);
+        expect(parser).toFailToParse("b");
       });
 
-      it("matches one-character literal correctly", function() {
-        var parser = PEG.buildParser('start = "a"', options);
+      it("does not advance position on success", function() {
+        var parser = PEG.buildParser('start = &"a" "a"', options);
 
-        expect(parser).toParse("a", "a");
-        expect(parser).toFailToParse("b");
+        expect(parser).toParse("a", [undefined, "a"]);
       });
 
-      it("matches multi-character literal correctly", function() {
-        var parser = PEG.buildParser('start = "abcd"', options);
+      it("does not influence expected strings on failure", function() {
+        var parser = PEG.buildParser('start = &"a"', options);
 
-        expect(parser).toParse("abcd", "abcd");
-        expect(parser).toFailToParse("ebcd");
-        expect(parser).toFailToParse("afcd");
-        expect(parser).toFailToParse("abgd");
-        expect(parser).toFailToParse("abch");
+        expect(parser).toFailToParse("b", { expected: [] });
       });
+    });
 
-      it("is case sensitive without the \"i\" flag", function() {
-        var parser = PEG.buildParser('start = "a"', options);
+    describe("negative simple predicate", function() {
+      it("matches correctly", function() {
+        var parser = PEG.buildParser('start = !"a" "b"', options);
 
-        expect(parser).toParse("a", "a");
-        expect(parser).toFailToParse("A");
+        expect(parser).toParse("b", [undefined, "b"]);
+        expect(parser).toFailToParse("a");
       });
 
-      it("is case insensitive with the \"i\" flag", function() {
-        var parser = PEG.buildParser('start = "a"i', options);
+      it("does not advance position on failure", function() {
+        var parser = PEG.buildParser('start = !"a" / "a"', options);
 
         expect(parser).toParse("a", "a");
-        expect(parser).toParse("A", "A");
       });
 
-      it("advances position on success", function() {
-        var parser = PEG.buildParser('start = "a" .', options);
+      it("does not influence expected strings on failure", function() {
+        var parser = PEG.buildParser('start = !"a"', options);
 
-        expect(parser).toParse("ab", ["a", "b"]);
+        expect(parser).toFailToParse("a", { expected: [] });
       });
+    });
 
-      it("sets expectation correctly on failure", function() {
-        var parser = PEG.buildParser('start = "a"', options);
+    describe("label", function() {
+      it("delegates to the expression", function() {
+        var parser = PEG.buildParser('start = a:"a"', options);
 
-        expect(parser).toFailToParse("b", {
-          expected: [{ type: "literal", value: "a", description: '"a"' }]
-        });
+        expect(parser).toParse("a", "a");
+        expect(parser).toFailToParse("b");
       });
     });
 
-    describe("class matching", function() {
-      it("matches empty class correctly", function() {
-        var parser = PEG.buildParser('start = []', options);
+    describe("sequence", function() {
+      it("matches correctly", function() {
+        var parser = PEG.buildParser('start = "a" "b" "c"', options);
 
-        expect(parser).toFailToParse("a");
+        expect(parser).toParse("abc", ["a", "b", "c"]);
       });
 
-      it("matches class with a character list correctly", function() {
-        var parser = PEG.buildParser('start = [abc]', options);
+      it("does not advance position on failure", function() {
+        var parser = PEG.buildParser('start = "a" "b" / "a"', options);
 
         expect(parser).toParse("a", "a");
-        expect(parser).toParse("b", "b");
-        expect(parser).toParse("c", "c");
-        expect(parser).toFailToParse("d");
       });
+    });
 
-      it("matches class with a range correctly", function() {
-        var parser = PEG.buildParser('start = [a-c]', options);
+    describe("action", function() {
+      it("tranforms the expression result by returnung a value", function() {
+        var parser = PEG.buildParser('start = "a" { return 42; }', options);
 
-        expect(parser).toParse("a", "a");
-        expect(parser).toParse("b", "b");
-        expect(parser).toParse("c", "c");
-        expect(parser).toFailToParse("d");
+        expect(parser).toParse("a", 42);
       });
 
-      it("matches inverted class correctly", function() {
-        var parser = PEG.buildParser('start = [^a]', options);
+      it("is not called when the expression does not match", function() {
+        var parser = PEG.buildParser(
+              'start = "a" { throw "Boom!"; } / "b"',
+              options
+            );
 
-        expect(parser).toFailToParse("a");
         expect(parser).toParse("b", "b");
       });
 
-      it("is case sensitive without the \"i\" flag", function() {
-        var parser = PEG.buildParser('start = [a]', options);
+      it("can use label variables", function() {
+        var parser = PEG.buildParser('start = a:"a" { return a; }', options);
 
         expect(parser).toParse("a", "a");
-        expect(parser).toFailToParse("A");
       });
 
-      it("is case insensitive with the \"i\" flag", function() {
-        var parser = PEG.buildParser('start = [a]i', options);
+      it("can use the |text| function to get the text matched by the expression", function() {
+        var parser = PEG.buildParser(
+              'start = "a" "b" "c" { return text(); }',
+              options
+            );
 
-        expect(parser).toParse("a", "a");
-        expect(parser).toParse("A", "A");
+        expect(parser).toParse("abc", "abc");
       });
 
-      it("advances position on success", function() {
-        var parser = PEG.buildParser('start = [a] .', options);
+      it("can use the |offset| function to get the current parse position", function() {
+        var parser = PEG.buildParser(
+              'start = "a" ("b" { return offset(); })',
+              options
+            );
 
-        expect(parser).toParse("ab", ["a", "b"]);
+        expect(parser).toParse("ab", ["a", 1]);
       });
 
-      it("sets expectation correctly on failure", function() {
-        var parser = PEG.buildParser('start = [a]', options);
+      it("can use the |line| and |column| functions to get the current line and column", function() {
+        var parser = PEG.buildParser([
+              '{ var result; }',
+              'start  = line (nl+ line)* { return result; }',
+              'line   = thing (" "+ thing)*',
+              'thing  = digit / mark',
+              'digit  = [0-9]',
+              'mark   = "x" { result = [line(), column()]; }',
+              'nl     = ("\\r" / "\\n" / "\\u2028" / "\\u2029")'
+            ].join("\n"), options);
 
-        expect(parser).toFailToParse("b", {
-          expected: [{ type: "class", value: "[a]", description: "[a]" }]
-        });
+        expect(parser).toParse("1\n2\n\n3\n\n\n4 5 x", [7, 5]);
+
+        /* Non-Unix newlines */
+        expect(parser).toParse("1\rx",   [2, 1]);   // Old Mac
+        expect(parser).toParse("1\r\nx", [2, 1]);   // Windows
+        expect(parser).toParse("1\n\rx", [3, 1]);   // mismatched
+
+        /* Strange newlines */
+        expect(parser).toParse("1\u2028x", [2, 1]);   // line separator
+        expect(parser).toParse("1\u2029x", [2, 1]);   // paragraph separator
       });
-    });
 
-    describe("any matching", function() {
-      it("matches correctly", function() {
-        var parser = PEG.buildParser('start = .', options);
+      it("can use variables defined in the initializer", function() {
+        var parser = PEG.buildParser([
+              '{ var v = 42 }',
+              'start = "a" { return v; }'
+            ].join("\n"), options);
 
-        expect(parser).toParse("a", "a");
+        expect(parser).toParse("a", 42);
       });
 
-      it("advances position on success", function() {
-        var parser = PEG.buildParser('start = . .', options);
+      it("can use the |expected| function to trigger an error", function() {
+        var parser = PEG.buildParser(
+              'start = "a" { expected("a"); }',
+              options
+            );
 
-        expect(parser).toParse("ab", ["a", "b"]);
+        expect(parser).toFailToParse("a", {
+          message:  'Expected a but "a" found.',
+          expected: [{ type: "other", description: "a" }],
+          found:    "a",
+          offset:   0,
+          line:     1,
+          column:   1
+        });
       });
 
-      it("sets expectation correctly on failure", function() {
-        var parser = PEG.buildParser('start = .', options);
+      it("can use the |error| function to trigger an error", function() {
+        var parser = PEG.buildParser(
+              'start = "a" { error("a"); }',
+              options
+            );
 
-        expect(parser).toFailToParse("", {
-          expected: [{ type: "any", description: "any character" }]
+        expect(parser).toFailToParse("a", {
+          message:  "a",
+          expected: null,
+          found:    "a",
+          offset:   0,
+          line:     1,
+          column:   1
         });
       });
+
+      it("can use functions defined in the initializer", function() {
+        var parser = PEG.buildParser([
+              '{ function f() { return 42; } }',
+              'start = "a" { return f(); }'
+            ].join("\n"), options);
+
+        expect(parser).toParse("a", 42);
+      });
+
+      it("can use the |parser| variable to access the parser object", function() {
+        var parser = PEG.buildParser(
+              'start = "a" { return parser; }',
+              options
+            );
+
+        expect(parser).toParse("a", parser);
+      });
+
+      it("can use options passed to the parser", function() {
+        var parser = PEG.buildParser(
+              'start = "a" { return options; }',
+              options
+            );
+
+        expect(parser).toParse("a", { a: 42 }, { a: 42 });
+      });
+    });
+
+    describe("choice", function() {
+      it("matches correctly", function() {
+        var parser = PEG.buildParser('start = "a" / "b" / "c"', options);
+
+        expect(parser).toParse("a", "a");
+        expect(parser).toParse("b", "b");
+        expect(parser).toParse("c", "c");
+        expect(parser).toFailToParse("d");
+      });
     });
 
     describe("error reporting", function() {