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ast.Expr

expressions

An expression statement: an expression standing on its own line whose value is discarded — a print(...) call, a docstring, a lone await.

Syntax

ast.Expr(value)

Almost every function call in a program body is an Expr wrapping a Call: when searching for calls, look into node.value. A docstring is an Expr too, the first one in the body, holding a string Constant. Do not confuse it with ast.Expression: that is the root of an 'eval'-mode tree, while Expr is an item of a module or function body list.

Examples

import ast
stmt = ast.parse('print(1)').body[0]
print(type(stmt).__name__, type(stmt.value).__name__)  # → Expr Call
doc = ast.parse('def f():\n    "Help text"').body[0].body[0]
print(type(doc).__name__, doc.value.value)  # → Expr Help text

See also

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