3 files changed, 71 insertions(+), 1 deletions(-)

A parse.go
R grammar_test.go => parse_test.go
A visit.go

@@ 0,0 1,10 @@
+package siberian
+
+// Matches returns true if m matches for input b. Note that if m allows a
+// zero match, Matches still returns true (a 0-match is still a match).
+// To check if m matches the full input b, make sure the matcher ends with
+// an EOF matcher (e.g. a Seq{Ms: []Matcher{SomeMatcher, EOF}}).
+func Matches(m Matcher, b []byte) bool {
+	n := m.Match(b, 0)
+	return n >= 0
+}

@@ 2,7 2,7 @@ package siberian
 
 import "testing"
 
-func TestGrammar_AB(t *testing.T) {
+func TestMatches_AB(t *testing.T) {
 	// Start = { As | B } .
 	// As = A+ .
 	// A = "a" .


@@ 38,6 38,59 @@ func TestGrammar_AB(t *testing.T) {
 			if n != c.len {
 				t.Errorf("want match of length %d, got %d", c.len, n)
 			}
+			matches := Matches(g, []byte(c.in))
+			if want := n >= 0; want != matches {
+				t.Errorf("want match? %t, got %t", want, matches)
+			}
+		})
+	}
+}
+
+func TestMatches_AB_EOF(t *testing.T) {
+	// Start = { As | B } .
+	// As = A+ .
+	// A = "a" .
+	// B = "b" .
+	g := &Seq{
+		Ms: []Matcher{
+			&Repeat{
+				Min: 0,
+				Max: -1,
+				M: &Alt{
+					Ms: []Matcher{
+						&Repeat{
+							Min: 1,
+							Max: -1,
+							M:   Equal("a"),
+						},
+						Equal("b"),
+					},
+				},
+			},
+			EOF,
+		},
+	}
+	cases := []matcherTest{
+		{"", 0},
+		{"a", 1},
+		{"b", 1},
+		{"c", -1},
+		{"aa", 2},
+		{"aaab", 4},
+		{"bb", 2},
+		{"bbaa", 4},
+		{"aaabc", -1},
+	}
+	for _, c := range cases {
+		t.Run(c.in, func(t *testing.T) {
+			n := g.Match([]byte(c.in), 0)
+			if n != c.len {
+				t.Errorf("want match of length %d, got %d", c.len, n)
+			}
+			matches := Matches(g, []byte(c.in))
+			if want := n >= 0; want != matches {
+				t.Errorf("want match? %t, got %t", want, matches)
+			}
 		})
 	}
 }

@@ 0,0 1,7 @@
+package siberian
+
+/*
+func Visit(m Matcher, fn func(m Matcher) Matcher) {
+
+}
+*/