unnecessary-generator-dict (C402)

Derived from the flake8-comprehensions linter.

Fix is always available.

What it does

Checks for unnecessary generators that can be rewritten as dict comprehensions.

Why is this bad?

It is unnecessary to use dict around a generator expression, since there are equivalent comprehensions for these types. Using a comprehension is clearer and more idiomatic.

Examples

dict((x, f(x)) for x in foo)

Use instead:

{x: f(x) for x in foo}

Fix safety

This rule's fix is marked as unsafe, as it may occasionally drop comments when rewriting the call. In most cases, though, comments will be preserved.