Parsing content as string

src/parser/parser_internals.nim

@@ -14,6 +14,20 @@ import ../utils/str
 
 # -- Parsing Functions
 
+func lookBack*(count: int): (Parser -> ParserResult) =
+  return func(parser: Parser): ParserResult =
+    let state = parser.state
+    let newIndex = state.position - 1
+
+    Parser(
+      state: ParserState(
+        stream: state.stream,
+        position: newIndex,
+        lastPosition: parser.state.position,
+      ),
+      tokens: parser.tokens,
+    ).ok()
+
 func ch*(expectedChars: set[char]): (Parser -> ParserResult) {.inline.} =
   return func(parser: Parser): ParserResult =
     let state = parser.state

src/parser/parser_types.nim

@@ -288,7 +288,7 @@ func highlightStreamPosition(stream: string, position: int): string =
 
 proc `$`*(x: ParserState): string =
   &"""ParserState(
-  stream: "{x.stream}",
+  stream: "{x.stream.highlightStreamPosition(x.position)}",
   position: {x.position},
   lastPosition: {x.lastPosition},
 )"""