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ast.BinOp

expressions

A binary operation node: left operand, operator and right operand — a + b, a * b, a | b and the other arithmetic and bitwise operations.

Syntax

ast.BinOp(left, op, right)

Precedence and parentheses are not stored — they become the shape of the tree: 1 + 2 * 3 gives a BinOp whose right is another BinOp with Mult. Comparisons (a < b) are Compare, and and/or are BoolOp, even though they look binary too. The operator sits in op as an instance (Add(), Mult()), so check isinstance(node.op, ast.Add) rather than comparing with '+'.

Examples

import ast
node = ast.parse('1 + 2 * 3', mode='eval').body
print(type(node.op).__name__, type(node.right).__name__)  # → Add BinOp
print(type(node.right.op).__name__)  # → Mult

import ast
node = ast.parse('(1 + 2) * 3', mode='eval').body
print(type(node.op).__name__, type(node.left).__name__)  # → Mult BinOp
print(ast.unparse(node))  # → (1 + 2) * 3

See also

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