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

calculators/builder-adversary-stateless/run-02/calc/parser.py

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+from dataclasses import dataclass
+from typing import Any
+
+
+class ParseError(Exception):
+    pass
+
+
+@dataclass
+class Num:
+    value: Any
+
+    def __repr__(self):
+        return f"Num({self.value!r})"
+
+
+@dataclass
+class BinOp:
+    op: str
+    left: Any
+    right: Any
+
+    def __repr__(self):
+        return f"BinOp({self.op!r}, {self.left!r}, {self.right!r})"
+
+
+@dataclass
+class Unary:
+    op: str
+    operand: Any
+
+    def __repr__(self):
+        return f"Unary({self.op!r}, {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 and tok.kind != kind:
+            raise ParseError(f"expected {kind}, got {tok.kind!r} ({tok.value!r})")
+        self._pos += 1
+        return tok
+
+    def parse(self):
+        node = self._expr()
+        tok = self._peek()
+        if tok.kind != 'EOF':
+            raise ParseError(f"unexpected token {tok.kind!r} ({tok.value!r})")
+        return node
+
+    def _expr(self):
+        # expr → term (('+' | '-') term)*
+        node = self._term()
+        while self._peek().kind in ('PLUS', 'MINUS'):
+            op = self._consume().value
+            right = self._term()
+            node = BinOp(op, node, right)
+        return node
+
+    def _term(self):
+        # term → unary (('*' | '/') unary)*
+        node = self._unary()
+        while self._peek().kind in ('STAR', 'SLASH'):
+            op = self._consume().value
+            right = self._unary()
+            node = BinOp(op, node, right)
+        return node
+
+    def _unary(self):
+        # unary → '-' unary | primary
+        if self._peek().kind == 'MINUS':
+            op = self._consume().value
+            operand = self._unary()
+            return Unary(op, operand)
+        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('LPAREN')
+            node = self._expr()
+            self._consume('RPAREN')
+            return node
+        if tok.kind == 'EOF':
+            raise ParseError("unexpected end of input")
+        raise ParseError(f"unexpected token {tok.kind!r} ({tok.value!r})")
+
+
+def parse(tokens) -> Any:
+    """Parse a token list from calc.lexer.tokenize into an AST.
+
+    AST node types:
+      Num(value)              — numeric literal
+      BinOp(op, left, right) — binary operation; op in {'+','-','*','/'}
+      Unary(op, operand)     — unary minus; op == '-'
+
+    Raises ParseError on malformed input.
+    """
+    return _Parser(tokens).parse()