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

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

@@ -0,0 +1,101 @@
+from dataclasses import dataclass
+from typing import Any, List
+
+
+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 is not None and tok.kind != kind:
+            raise ParseError(f"expected {kind}, got {tok.kind!r} ({tok.value!r})")
+        self._pos += 1
+        return tok
+
+    def _parse_expr(self):
+        node = self._parse_term()
+        while self._peek().kind in ('PLUS', 'MINUS'):
+            op = self._consume().value
+            right = self._parse_term()
+            node = BinOp(op, node, right)
+        return node
+
+    def _parse_term(self):
+        node = self._parse_unary()
+        while self._peek().kind in ('STAR', 'SLASH'):
+            op = self._consume().value
+            right = self._parse_unary()
+            node = BinOp(op, node, right)
+        return node
+
+    def _parse_unary(self):
+        if self._peek().kind == 'MINUS':
+            op = self._consume().value
+            operand = self._parse_unary()
+            return Unary(op, operand)
+        return self._parse_primary()
+
+    def _parse_primary(self):
+        tok = self._peek()
+        if tok.kind == 'NUMBER':
+            self._consume()
+            return Num(tok.value)
+        if tok.kind == 'LPAREN':
+            self._consume()
+            node = self._parse_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} ({tok.value!r})")
+
+
+def parse(tokens: list):
+    """Parse a token list produced by lexer.tokenize() into an AST.
+
+    Returns one of: Num(value), BinOp(op, left, right), Unary(op, operand).
+    Raises ParseError on malformed input.
+    """
+    p = _Parser(tokens)
+    if p._peek().kind == 'EOF':
+        raise ParseError("empty input")
+    node = p._parse_expr()
+    if p._peek().kind != 'EOF':
+        raise ParseError(f"unexpected token {p._peek().kind!r} ({p._peek().value!r})")
+    return node