* Add sets.is_set() to test whether an arbitrary object is a set.
Since using sets requires special API, it can be useful to determine
whether an object is a set so special handling can be used.
For example, if a method wants to be able to take a list or a set.
Buildifier 0.12.0 includes initial support for reformatting .bzl files.
- Reformat all the bzl files.
- Expand the travis check to check the .bzl files also.
Even though it's not great to use type checks, they are frequently useful for
checking input types of macros.
Because there is no standard way of checking types, at least 2 types of checks
are used:
- `type(foo) == type([])`
- `type(foo) == "list"`
The first option is not very readable and the second option seem to be relying
on an Bazel implementation detail. Encapsulating type checks into this library
enables consistent and easy to understand type checking without explicitly
relying on implementation details.
