diff --git a/scanner/scanner.go b/scanner/scanner.go
index 2fc3b27..394eeb0 100644
--- a/scanner/scanner.go
+++ b/scanner/scanner.go
@@ -104,25 +104,25 @@ func (s *Scanner) Scan() (tok token.Token) {
 	s.tokBuf.Reset()
 	s.tokPos = s.currPos.Offset - s.lastCharLen
 
-	if isLetter(ch) {
+	switch {
+	case isLetter(ch):
 		tok = token.IDENT
 		lit := s.scanIdentifier()
 		if lit == "true" || lit == "false" {
 			tok = token.BOOL
 		}
-	}
 
-	if isDigit(ch) {
+	case isDigit(ch):
 		s.scanNumber()
 		// TODO(arslan)
-	}
-
-	switch ch {
-	case eof:
-		tok = token.EOF
-	case '"':
-		tok = token.STRING
-		s.scanString()
+	default:
+		switch ch {
+		case eof:
+			tok = token.EOF
+		case '"':
+			tok = token.STRING
+			s.scanString()
+		}
 	}
 
 	s.tokEnd = s.currPos.Offset
diff --git a/scanner/scanner_test.go b/scanner/scanner_test.go
index 4f69088..4d30050 100644
--- a/scanner/scanner_test.go
+++ b/scanner/scanner_test.go
@@ -98,3 +98,61 @@ func TestString(t *testing.T) {
 
 	testTokenList(t, tokenList)
 }
+
+func TestNumber(t *testing.T) {
+	t.SkipNow()
+	var tokenList = []tokenPair{
+		{token.NUMBER, "0"},
+		{token.NUMBER, "1"},
+		{token.NUMBER, "9"},
+		{token.NUMBER, "42"},
+		{token.NUMBER, "1234567890"},
+		{token.NUMBER, "00"},
+		{token.NUMBER, "01"},
+		{token.NUMBER, "07"},
+		{token.NUMBER, "042"},
+		{token.NUMBER, "01234567"},
+		{token.NUMBER, "0x0"},
+		{token.NUMBER, "0x1"},
+		{token.NUMBER, "0xf"},
+		{token.NUMBER, "0x42"},
+		{token.NUMBER, "0x123456789abcDEF"},
+		{token.NUMBER, "0x" + f100},
+		{token.NUMBER, "0X0"},
+		{token.NUMBER, "0X1"},
+		{token.NUMBER, "0XF"},
+		{token.NUMBER, "0X42"},
+		{token.NUMBER, "0X123456789abcDEF"},
+		{token.NUMBER, "0X" + f100},
+		{token.FLOAT, "0."},
+		{token.FLOAT, "1."},
+		{token.FLOAT, "42."},
+		{token.FLOAT, "01234567890."},
+		{token.FLOAT, ".0"},
+		{token.FLOAT, ".1"},
+		{token.FLOAT, ".42"},
+		{token.FLOAT, ".0123456789"},
+		{token.FLOAT, "0.0"},
+		{token.FLOAT, "1.0"},
+		{token.FLOAT, "42.0"},
+		{token.FLOAT, "01234567890.0"},
+		{token.FLOAT, "0e0"},
+		{token.FLOAT, "1e0"},
+		{token.FLOAT, "42e0"},
+		{token.FLOAT, "01234567890e0"},
+		{token.FLOAT, "0E0"},
+		{token.FLOAT, "1E0"},
+		{token.FLOAT, "42E0"},
+		{token.FLOAT, "01234567890E0"},
+		{token.FLOAT, "0e+10"},
+		{token.FLOAT, "1e-10"},
+		{token.FLOAT, "42e+10"},
+		{token.FLOAT, "01234567890e-10"},
+		{token.FLOAT, "0E+10"},
+		{token.FLOAT, "1E-10"},
+		{token.FLOAT, "42E+10"},
+		{token.FLOAT, "01234567890E-10"},
+	}
+
+	testTokenList(t, tokenList)
+}