Accept escaped hyphens, even outside character class

Makefile

@@ -5,9 +5,13 @@ fmt:
 	go fmt ./...
 vet: fmt
 	go vet ./...
-buildLib: vet
+buildLibUnopt: vet
 	go build -gcflags="all=-N -l" ./...
-buildCmd: buildLib
+unopt: buildLibUnopt
 	go build -C kg/ -gcflags="all=-N -l" -o kg ./...
+buildLib: vet
+	go build ./...
+buildCmd: buildLib
+	go build -C kg/ -o kg ./...
 test: buildCmd
 	go test -v ./...

regex/postfixNode.go

@@ -131,13 +131,9 @@ func newEscapedNode(c rune, inCharClass bool) (postfixNode, error) {
 	case 'v': // Vertical tab
 		toReturn.nodetype = characterNode
 		toReturn.contents = append(toReturn.contents, rune(11))
-	case '-': // Literal hyphen - only in character class
-		if inCharClass {
-			toReturn.nodetype = characterNode
-			toReturn.contents = append(toReturn.contents, '-')
-		} else {
-			return postfixNode{}, fmt.Errorf("invalid escape character")
-		}
+	case '-': // Literal hyphen
+		toReturn.nodetype = characterNode
+		toReturn.contents = append(toReturn.contents, '-')
 	default: // None of the above - append it as a regular character
 		if isNormalChar(c) { // Normal characters cannot be escaped
 			return postfixNode{}, fmt.Errorf("invalid escape character")