Code Style

Formatting

Run ./style.sh in the top-level directory. ./style.sh --fix will attempt to auto-format.

General

• Prefer longer variable names. Avoid abbreviations. We have autocomplete for a reason!

C++

• Adhere to all clang tidy checks defined in .clang-tidy. This is tested by the CI.
• Style syntax with the clang format defined by .clang-format. This is tested by the CI.
• Never use raw pointers, prefer smart pointers (usually std::shared_ptr).
• Check if something exists in the standard library before you reinvent the wheel!
• Prefer static_cast etc. instead of C style cast
• Use auto on iterator types (ranged for) and when the type is obvious, for example casting or std::make_shared
• Pass primitives by value (int, float, etc.) and complex types by reference or smart pointers
• Do not use references (&) types for out parameters in functions, prefer returning a struct
• Prefer using an explicit struct instead of std::pair or std::tuple
• Use structured binding when possible (e.g. iterating named map, unpacking a std::pair, …)
• Avoid std::bind, use an explicit lambda
• Prefer PascalCase for things like classes and camelCase for things like member variables. This is tested by the CI.

Python

• Currently black and mypy are used. This is tested by the CI.
• If you are writing a function, please use type hinting for the signature. For other places, only use if necessary, for example a situation where the types are confusing.
• Black is an autoformating tool that will control the format of your code
• MyPy is a static type analysis tool that will make sure you don’t violate type hinted functions
• Document your code! Use the reST standard specifically
• Prefer snake_case for regular python classes, functions, and variables and UPPER_CASE for constants

Here is a good concrete example:

def pos_distance_to(self, p: SE3) -> float:
    """
    Get the euclidean distance from the position of this SE3 pose to the position of another SE3 pose.
    :param p: another SE3 pose object
    :returns: euclidean distance between the two SE3 poses
    """
    return np.linalg.norm(p.position_vector() - self.position_vector())