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ast.NotEq

operators

The != comparison operator in the ops list of a Compare node.

Syntax

ast.NotEq()

Comparisons in ast are not binary: a != b != c is one Compare with two NotEq in ops and two comparators, not nested nodes, and it means a != b and b != c, so a and c may still be equal. The operator sits in a list, so testing for != is isinstance(n.ops[i], ast.NotEq), not an op field. The old <> is gone in Python 3: ast.parse raises SyntaxError.

Examples

import ast
n = ast.parse('a != b != c', mode='eval').body
print(type(n).__name__, [type(o).__name__ for o in n.ops], len(n.comparators))  # → Compare ['NotEq', 'NotEq'] 2
print(1 != 2 != 1)  # → True

See also

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