mypy.renaming.LimitedVariableRenameVisitor

Perform some limited variable renaming in with statements. This allows reusing a variable in multiple with statements with different types. For example, the two instances of 'x' can have incompatible types: with C() as x: f(x) with D() as x: g(x) The above code gets renamed conceptually into this (not valid Python!): with C() as x': f(x') with D() as x: g(x) If there's a reference to a variable defined in 'with' outside the statement, or if there's any trickiness around variable visibility (e.g. function definitions), we give up and won't perform renaming. The main use case is to allow binding both readable and writable binary files into the same variable. These have different types: with open(fnam, 'rb') as f: ... with open(fnam, 'wb') as f: ...