Refactor

2 files changed, 31 insertions, 6 deletions

diff --git a/spec/parser.go b/spec/parser.go
index 8b825bf..e749d72 100644
--- a/spec/parser.go
+++ b/spec/parser.go
@@ -8,8 +8,9 @@ import (
 )
 
 type RootNode struct {
-	Productions []*ProductionNode
-	Fragments   []*FragmentNode
+	Productions    []*ProductionNode
+	LexProductions []*ProductionNode
+	Fragments      []*FragmentNode
 }
 
 type ProductionNode struct {
@@ -18,6 +19,13 @@ type ProductionNode struct {
 	RHS       []*AlternativeNode
 }
 
+func (n *ProductionNode) isLexical() bool {
+	if len(n.RHS) == 1 && len(n.RHS[0].Elements) == 1 && n.RHS[0].Elements[0].Pattern != "" {
+		return true
+	}
+	return false
+}
+
 type AlternativeNode struct {
 	Elements  []*ElementNode
 	Directive *DirectiveNode
@@ -112,6 +120,7 @@ func (p *parser) parseRoot() *RootNode {
 	}()
 
 	var prods []*ProductionNode
+	var lexProds []*ProductionNode
 	var fragments []*FragmentNode
 	for {
 		fragment := p.parseFragment()
@@ -122,7 +131,11 @@ func (p *parser) parseRoot() *RootNode {
 
 		prod := p.parseProduction()
 		if prod != nil {
-			prods = append(prods, prod)
+			if prod.isLexical() {
+				lexProds = append(lexProds, prod)
+			} else {
+				prods = append(prods, prod)
+			}
 			continue
 		}
 
@@ -132,8 +145,9 @@ func (p *parser) parseRoot() *RootNode {
 	}
 
 	return &RootNode{
-		Productions: prods,
-		Fragments:   fragments,
+		Productions:    prods,
+		LexProductions: lexProds,
+		Fragments:      fragments,
 	}
 }
 
diff --git a/spec/parser_test.go b/spec/parser_test.go
index 89cc4d1..c696af0 100644
--- a/spec/parser_test.go
+++ b/spec/parser_test.go
@@ -82,7 +82,7 @@ func TestParse(t *testing.T) {
 			caption: "single production is a valid grammar",
 			src:     `a: "a";`,
 			ast: &RootNode{
-				Productions: []*ProductionNode{
+				LexProductions: []*ProductionNode{
 					prod("a", alt(pat("a"))),
 				},
 			},
@@ -109,6 +109,8 @@ id: "[A-Za-z_][0-9A-Za-z_]*";
 						alt(pat(`\(`), id("e"), pat(`)`)),
 						alt(id("id")),
 					),
+				},
+				LexProductions: []*ProductionNode{
 					prod("id",
 						alt(pat(`[A-Za-z_][0-9A-Za-z_]*`)),
 					),
@@ -177,6 +179,8 @@ fragment words: "[A-Za-z\u{0020}]+";
 					prod("s",
 						alt(id("tagline")),
 					),
+				},
+				LexProductions: []*ProductionNode{
 					prod("tagline",
 						alt(pat(`\f{words} IS OUT THERE.`)),
 					),
@@ -221,6 +225,8 @@ whitespace: "\u{0020}+" #skip;
 						alt(id("pop_m1")),
 						alt(id("pop_m2")),
 					),
+				},
+				LexProductions: []*ProductionNode{
 					prod("push_m1",
 						withAltDir(
 							alt(pat(`->`)),
@@ -311,6 +317,8 @@ bar: "bar";
 							dir("ast", treeParam("bar_list", pos(1))),
 						),
 					),
+				},
+				LexProductions: []*ProductionNode{
 					prod("foo",
 						alt(pat("foo")),
 					),
@@ -377,6 +385,9 @@ func testRootNode(t *testing.T, root, expected *RootNode) {
 	for i, prod := range root.Productions {
 		testProductionNode(t, prod, expected.Productions[i])
 	}
+	for i, prod := range root.LexProductions {
+		testProductionNode(t, prod, expected.LexProductions[i])
+	}
 }
 
 func testProductionNode(t *testing.T, prod, expected *ProductionNode) {