Replaces the start and end terminals of strings with a single terminal, with " as a literal for it

2 files changed, 17 insertions, 16 deletions

diff --git a/subex/parse.go b/subex/parse.go
index 9e47e0b..b1d54ac 100644
--- a/subex/parse.go
+++ b/subex/parse.go
@@ -39,7 +39,7 @@ func parseTerminatorAtomLiteral(termType rune, l RuneReader) walk.Atom {
 		case '@':
 			return expectBracket(l, walk.ArrayBegin, walk.ArrayEnd)
 		case '~':
-			return expectBracket(l, walk.StartString{}, walk.EndString{})
+			return expectBracket(l, walk.StringTerminal{}, walk.StringTerminal{})
 		case '#':
 			return expectBracket(l, walk.MapBegin, walk.MapEnd)
 		default:
@@ -193,6 +193,8 @@ func parseReplacement(l RuneReader) (output []OutputContent) {
 				for _, literal := range literals {
 					output = append(output, OutputAtomLiteral {literal})
 				}
+			case '"':
+				output = append(output, OutputAtomLiteral {walk.StringTerminal{}})
 			default:
 				output = append(output, OutputAtomLiteral{atom: walk.StringAtom(r)})
 		}
@@ -218,6 +220,9 @@ func parseRangeSubex(l RuneReader) map[walk.Atom]walk.Atom {
 			literals := parseNonStringLiteral(l)
 			froms = append(froms, literals...)
 			continue
+		} else if fromsStart == '"' {
+			froms = append(froms, walk.StringTerminal{})
+			continue
 		} else {
 			atom := parseTerminatorAtomLiteral(fromsStart, l)
 			if atom != nil {
@@ -252,6 +257,9 @@ func parseRangeSubex(l RuneReader) map[walk.Atom]walk.Atom {
 				literals := parseNonStringLiteral(l)
 				tos = append(tos, literals...)
 				continue
+			} else if tosStart == '"' {
+				tos = append(tos, walk.StringTerminal{})
+				continue
 			} else {
 				atom := parseTerminatorAtomLiteral(tosStart, l)
 				if atom != nil {
@@ -307,6 +315,8 @@ func parseSubex(l RuneReader, minPower int) SubexAST {
 			lhs = SubexASTOutput{replacement}
 		case '.':
 			lhs = SubexASTCopyAny{}
+		case '"':
+			lhs = SubexASTCopyAtom {walk.StringTerminal{}}
 		case '@', '#', '~':
 			lhs = SubexASTCopyAtom{atom: parseTerminatorAtomLiteral(r, l)}
 		case '`':
diff --git a/walk/walk.go b/walk/walk.go
index 72fbe11..5c1ca75 100644
--- a/walk/walk.go
+++ b/walk/walk.go
@@ -99,22 +99,19 @@ func (value ValueNumber) String() string {
 }
 func (value ValueNumber) atomness() {}
 
-type StartString struct {}
-func (value StartString) atomness() {}
-
-type EndString struct {}
-func (value EndString) atomness() {}
+type StringTerminal struct {}
+func (value StringTerminal) atomness() {}
 
 type StringAtom rune
 func (value StringAtom) atomness() {}
 
 type ValueString string
 func (value ValueString) Pieces(out chan<- Atom) {
-	out<-StartString{}
+	out<-StringTerminal{}
 	for _, char := range value {
 		out<-StringAtom(char)
 	}
-	out<-EndString{}
+	out<-StringTerminal{}
 }
 func (value ValueString) String() string {
 	return fmt.Sprintf("\"%s\"", string(value))
@@ -456,7 +453,6 @@ type CompoundError int
 
 const (
 	CompoundRuneOutsideString CompoundError = iota
-	CompoundEndStringOutsideString
 	CompoundUnknownAtom
 	CompoundMissingEnd
 	CompoundInvalidStringAtom
@@ -466,8 +462,6 @@ func (err CompoundError) Error() string {
 	switch err {
 		case CompoundRuneOutsideString:
 			return "Compound Error: Rune Outside String"
-		case CompoundEndStringOutsideString:
-			return "Compound Error: End String Outside String"
 		case CompoundUnknownAtom:
 			return "Compound Error: Unknown Atom"
 		case CompoundMissingEnd:
@@ -508,10 +502,7 @@ func Compound(in <-chan Atom) <-chan CompoundResult {
 				case StringAtom:
 					out<-CompoundResult{nil, CompoundRuneOutsideString}
 					break outer
-				case EndString:
-					out<-CompoundResult{nil, CompoundEndStringOutsideString}
-					break outer
-				case StartString:
+				case StringTerminal:
 				default:
 					out<-CompoundResult{nil, CompoundUnknownAtom}
 					break outer
@@ -525,7 +516,7 @@ func Compound(in <-chan Atom) <-chan CompoundResult {
 					break outer
 				}
 				switch v := atom.(type) {
-					case EndString:
+					case StringTerminal:
 						break loop
 					case StringAtom:
 						builder.WriteRune(rune(v))