willmcgugan · August 3, 2025 09:00 · Aug 3, 2025
diff --git a/sequence_validator.py b/sequence_validator.py
@@ -0,0 +1,48 @@
+from typing import Generator
+
+
+class SequenceValidator:
+    def __init__(self) -> None:
+        self._generator = self.check()
+        self._consumed = -1
+        next(self._generator)
+
+    def feed(self, text: str) -> tuple[int, bool | None]:
+        try:
+            for character in text:
+                self._consumed += 1
+                self._generator.send(character)
+
+        except StopIteration as stop_iteration:
+            return (self._consumed, stop_iteration.value)
+        else:
+            return (self._consumed, None)
+
+    def check(self) -> Generator[None, str, bool | None]:
+        return False
+        yield
+
+
+class BracesNumber(SequenceValidator):
+    """A [ followed by 0 or more digits followed by ]"""
+
+    def check(self) -> Generator[None, str, bool | None]:
+        if (yield) != "[":
+            return False
+        while (character := (yield)) in "0123456789":
+            pass
+        return character == "]"
+
+
+data = "[123]"
+validator = BracesNumber()
+for character in data:
+    print(validator.feed(character))
+
+print("---")
+
+
+data = "[123)"
+validator = BracesNumber()
+for character in data:
+    print(validator.feed(character))