Nodes now accept TextView objects upon instatiation

DHParser/parser.py

@@ -77,7 +77,7 @@ except ImportError:
 from DHParser.toolkit import is_logging, log_dir, logfile_basename, escape_re, sane_parser_name
 from DHParser.syntaxtree import WHITESPACE_PTYPE, TOKEN_PTYPE, ZOMBIE_PARSER, ParserBase, \
     Node, TransformationFunc
-from DHParser.toolkit import load_if_file, error_messages, line_col
+from DHParser.toolkit import TextView, load_if_file, error_messages, line_col
 
 __all__ = ('PreprocessorFunc',
            'HistoryRecord',
@@ -233,7 +233,7 @@ def add_parser_guard(parser_func):
         def memoized(parser, location):
             node = parser.visited[location]
             rlen = location - (0 if node is None else node.len)
-            rest = grammar.document__[-rlen:] if rlen else ''
+            rest = TextView(grammar.document__, -rlen) if rlen else ''
             return node, rest
             # NOTE: An older and simpler implementation of memoization
             # relied on `parser.visited[location] == node, rest`. Although,
@@ -409,7 +409,7 @@ class Parser(ParserBase, metaclass=ParserMetaClass):
         self.cycle_detection = set()     # type: Set[Callable]
         return self
 
-    def __call__(self, text: str) -> Tuple[Node, str]:
+    def __call__(self, text: TextView) -> Tuple[Node, TextView]:
         """Applies the parser to the given `text` and returns a node with
         the results or None as well as the text at the position right behind
         the matching string."""

DHParser/syntaxtree.py

@@ -31,7 +31,7 @@ except ImportError:
     from .typing34 import AbstractSet, Any, ByteString, Callable, cast, Container, Dict, \
         Iterator, List, NamedTuple, Sequence, Union, Text, Tuple
 
-from DHParser.toolkit import is_logging, log_dir, line_col, identity
+from DHParser.toolkit import is_logging, log_dir, TextView, line_col, identity
 
 __all__ = ('WHITESPACE_PTYPE',
            'MockParser',
@@ -129,8 +129,8 @@ ZOMBIE_PARSER = ZombieParser()
 Error = NamedTuple('Error', [('pos', int), ('msg', str)])
 
 ChildrenType = Tuple['Node', ...]
-StrictResultType = Union[ChildrenType, str]
-ResultType = Union[ChildrenType, 'Node', str, None]
+StrictResultType = Union[ChildrenType, TextView, str]
+ResultType = Union[ChildrenType, 'Node', TextView, str, None]
 
 
 def flatten_sxpr(sxpr: str) -> str:
@@ -250,7 +250,8 @@ class Node:
         # assert ((isinstance(result, tuple) and all(isinstance(child, Node) for child in result))
         #         or isinstance(result, Node)
         #         or isinstance(result, str)), str(result)
-        self._result = (result,) if isinstance(result, Node) else result or ''  # type: StrictResultType
+        self._result = (result,) if isinstance(result, Node) else str(result) \
+            if isinstance(result, TextView) else result or ''  # type: StrictResultType
         self.children = cast(ChildrenType, self._result) \
             if isinstance(self._result, tuple) else cast(ChildrenType, ())  # type: ChildrenType
         self.error_flag = any(r.error_flag for r in self.children)  # type: bool

DHParser/toolkit.py

@@ -155,7 +155,7 @@ class TextView:
 
     def __init__(self, text: str, begin: Optional[int] = 0, end: Optional[int] = None) -> None:
         self.text = text  # type: str
-        self.begin = begin or 0  # type: int
+        self.begin = begin or 0  # type: int # TODO: Negative Values!!!
         self.end = end or len(text)  # type: int
 
     def __str__(self):