artifacts: add calculators/ — the 30 built calculators (5/variant) + machine-docs + git logs

calculators/builder-adversary/run-05/calc/parser.py

@@ -0,0 +1,104 @@
+from dataclasses import dataclass
+from typing import Union
+
+
+class ParseError(Exception):
+    pass
+
+
+@dataclass
+class Num:
+    value: Union[int, float]
+
+    def __repr__(self):
+        return f"Num({self.value})"
+
+
+@dataclass
+class BinOp:
+    op: str
+    left: object
+    right: object
+
+    def __repr__(self):
+        return f"BinOp({self.op}, {self.left!r}, {self.right!r})"
+
+
+@dataclass
+class Unary:
+    op: str
+    operand: object
+
+    def __repr__(self):
+        return f"Unary({self.op}, {self.operand!r})"
+
+
+class _Parser:
+    def __init__(self, tokens):
+        self.tokens = tokens
+        self.pos = 0
+
+    def _peek(self):
+        return self.tokens[self.pos]
+
+    def _consume(self, kind=None):
+        tok = self.tokens[self.pos]
+        if kind is not None and tok.kind != kind:
+            raise ParseError(f"expected {kind!r}, got {tok.kind!r}")
+        self.pos += 1
+        return tok
+
+    def _expr(self):
+        left = self._term()
+        while self._peek().kind in ('PLUS', 'MINUS'):
+            op = self._consume().kind
+            right = self._term()
+            left = BinOp(op, left, right)
+        return left
+
+    def _term(self):
+        left = self._unary()
+        while self._peek().kind in ('STAR', 'SLASH'):
+            op = self._consume().kind
+            right = self._unary()
+            left = BinOp(op, left, right)
+        return left
+
+    def _unary(self):
+        if self._peek().kind == 'MINUS':
+            self._consume()
+            return Unary('MINUS', self._unary())
+        return self._primary()
+
+    def _primary(self):
+        tok = self._peek()
+        if tok.kind == 'NUMBER':
+            self._consume()
+            return Num(tok.value)
+        if tok.kind == 'LPAREN':
+            self._consume()
+            node = self._expr()
+            if self._peek().kind != 'RPAREN':
+                raise ParseError(f"expected ')', got {self._peek().kind!r}")
+            self._consume()
+            return node
+        raise ParseError(f"unexpected token {tok.kind!r}")
+
+
+def parse(tokens) -> object:
+    """Parse a token list into an AST.
+
+    Nodes:
+      Num(value)              — numeric literal (int or float)
+      BinOp(op, left, right)  — binary op; op in {'PLUS','MINUS','STAR','SLASH'}
+      Unary(op, operand)      — unary minus; op == 'MINUS'
+
+    Raises ParseError on malformed input.
+    """
+    p = _Parser(tokens)
+    if p._peek().kind == 'EOF':
+        raise ParseError("empty input")
+    node = p._expr()
+    if p._peek().kind != 'EOF':
+        raise ParseError(f"unexpected token {p._peek().kind!r} after expression")
+    return node