1 files changed, 73 insertions, 30 deletions
diff --git a/main/parse.go b/main/parse.go
index 141ae7e..36bd3ee 100644
--- a/main/parse.go
+++ b/main/parse.go
@@ -44,13 +44,7 @@ func (p *parser) parseSubex() subex.SubexAST {
 	if subexProgramToken.typ != TokenSubex {
 		panic("Missing subex from substitution")
 	}
-	var subexProgram string
-	if delim.val == "=" || delim.val == "~" || delim.val == "\"" || delim.val == "`" || delim.val == "^" {
-		subexProgram = delim.val + subexProgramToken.val + delim.val
-	} else {
-		subexProgram = subexProgramToken.val
-	}
-	reader := subex.NewStringRuneReader(subexProgram)
+	reader := subex.NewStringRuneReader(subexProgramToken.val)
 	subexAST := subex.Parse(reader)
 	delim = p.next()
 	if delim.typ != TokenSubstituteDelimiter {
@@ -65,41 +59,90 @@ func (p *parser) parseBasicCommand(commands []Command, commandChar rune) []Comma
 			return append(commands, PrintValueCommand{})
 		case 'd':
 			return append(commands, DeleteValueCommand{})
-		case 'D':
-			return append(commands, DeletePathCommand{})
 		case 'n':
-			return append(commands, NextCommand{})
-		case 'N':
-			return append(commands, AppendNextCommand{})
-		case 's', 'S':
+			delim := p.peek()
+			if delim.typ != TokenSubstituteDelimiter {
+				return append(commands, NextCommand{})
+			}
 			ast := p.parseSubex()
 			subex := subex.CompileTransducer(ast)
-			switch commandChar {
-				case 's':
-					return append(commands, SubstituteValueCommand {subex}, JumpCommand {len(commands) + 3})
-				case 'S':
-					return append(commands, SubstitutePathCommand {subex}, JumpCommand {len(commands) + 3})
-				default:
-					panic("Unreachable!?!?")
+			return append(commands, SubstituteNextCommand {subex}, JumpCommand {len(commands) + 3})
+		case 'N':
+			delim := p.peek()
+			if delim.typ != TokenSubstituteDelimiter {
+				return append(commands, AppendNextCommand{})
 			}
+			ast := p.parseSubex()
+			subex := subex.CompileTransducer(ast)
+			return append(commands, SubstituteAppendNextCommand {subex}, JumpCommand {len(commands) + 3})
+		case 'm':
+			return append(commands, MergeCommand{})
+		case 'M':
+			ast := p.parseSubex()
+			subex := subex.CompileTransducer(ast)
+			return append(commands, FullMergeCommand {subex}, JumpCommand {len(commands) + 3})
+		case 's':
+			ast := p.parseSubex()
+			subex := subex.CompileTransducer(ast)
+			return append(commands, SubstituteValueCommand {subex}, JumpCommand {len(commands) + 3})
 		case 'o':
 			return append(commands, NoopCommand{})
 		case 'x':
-			return append(commands, SwapXRegCommand{})
+			delim := p.peek()
+			if delim.typ != TokenSubstituteDelimiter {
+				return append(commands, SwapXRegCommand{})
+			}
+			ast := p.parseSubex()
+			subex := subex.CompileTransducer(ast)
+			return append(commands, SubstituteToXRegCommand {subex}, JumpCommand {len(commands) + 3})
 		case 'X':
-			return append(commands, AppendXRegCommand{})
+			delim := p.peek()
+			if delim.typ != TokenSubstituteDelimiter {
+				return append(commands, AppendXRegCommand{})
+			}
+			ast := p.parseSubex()
+			subex := subex.CompileTransducer(ast)
+			return append(commands, SubstituteAppendXRegCommand {subex}, JumpCommand {len(commands) + 3})
 		case 'y':
-			return append(commands, SwapYRegCommand{})
+			delim := p.peek()
+			if delim.typ != TokenSubstituteDelimiter {
+				return append(commands, SwapYRegCommand{})
+			}
+			ast := p.parseSubex()
+			subex := subex.CompileTransducer(ast)
+			return append(commands, SubstituteToYRegCommand {subex}, JumpCommand {len(commands) + 3})
 		case 'Y':
-			return append(commands, AppendYRegCommand{})
+			delim := p.peek()
+			if delim.typ != TokenSubstituteDelimiter {
+				return append(commands, AppendYRegCommand{})
+			}
+			ast := p.parseSubex()
+			subex := subex.CompileTransducer(ast)
+			return append(commands, SubstituteAppendYRegCommand {subex}, JumpCommand {len(commands) + 3})
 		case 'z':
-			return append(commands, SwapZRegCommand{})
+			delim := p.peek()
+			if delim.typ != TokenSubstituteDelimiter {
+				return append(commands, SwapZRegCommand{})
+			}
+			ast := p.parseSubex()
+			subex := subex.CompileTransducer(ast)
+			return append(commands, SubstituteToZRegCommand {subex}, JumpCommand {len(commands) + 3})
 		case 'Z':
-			return append(commands, AppendZRegCommand{})
-		case 'k':
-			return append(commands, SwapPathCommand{})
-		case 'K':
-			return append(commands, AppendPathCommand{})
+			delim := p.peek()
+			if delim.typ != TokenSubstituteDelimiter {
+				return append(commands, AppendZRegCommand{})
+			}
+			ast := p.parseSubex()
+			subex := subex.CompileTransducer(ast)
+			return append(commands, SubstituteAppendZRegCommand {subex}, JumpCommand {len(commands) + 3})
+		case 'a':
+			return append(commands, IsStartCommand{}, JumpCommand {len(commands) + 3})
+		case 'A':
+			return append(commands, IsPrevStartCommand{}, JumpCommand {len(commands) + 3})
+		case 'e':
+			return append(commands, IsEndCommand{}, JumpCommand {len(commands) + 3})
+		case 'E':
+			return append(commands, IsNextEndCommand{}, JumpCommand {len(commands) + 3})
 		case ':':
 			labelToken := p.next()
 			if labelToken.typ != TokenLabel {