Python functions naming: an algorithm
The Motivation Part
Well, we all know that clear naming is crucial for readability.
Still, I see a function named get_user in every project. I renamed it to fetch_user_from_db in one project and toclear_user_data in another. As you can see, the functions had the same name but had nothing in common.
The most important part of a function name is a verb. The most popular verb is “get”, and it is a very lazy choice: it gives us none of the additional info. For example, you can replace “get” with “fetch”, then I would know that the function receives data from the network/disk.
Below you can see The Naming Algorithm: a connection between common verbs and their meanings. Use it for great good and forget about “get” and “process”.
The Naming Algorithm
- Is the function a test? ->
test_<entity>_<behavior>.
2. Does the function has a @property decorator? -> don’t use a verb in the function name.
3. Does the function use a disk or a network:
3.1. … to store data? -> save_to, send, write_to
3.2. … to receive data? -> fetch, load, read
4. Does the function output any data? -> print, output
5. Returns boolean value? -> is_, has_/have_, can_, check_if_<entity>_<characteristic>
6. Aggregates data? -> calculate, extract, analyze
7. Put data from one form to another:
7.1. Creates a single meaningful object? -> create
7.2. Fills an existing object with data? -> initialize, configure
7.3. Clean raw data? -> clean
7.4. Receive a string as input? -> parse
7.5. Return a string as output? -> render
7.6. Return an iterator as output? ->iter
7.7. Mutates its arguments or some global state? -> update, mutate, add, remove, insert, set
7.8. Return a list of errors? -> validate
7.9. Checks data items recursively? -> walk
7.10. Finds appropriate item in data? -> find, search, match
7.11. Transform data type? -> <something>_to_<something_else>
7.12. None of the above, but still works with data? -> Check one of those: morph, compose, prepare, extract, generate, initialize, filter, map, aggregate, export, import, normalize, calculate .
The Blacklist
Well, you might be surprised, but I don’t recommend using these verbs in functions names: get, run, process, make, handle, do, main, compare.
They all are too generic and has a more precise analogue almost always.
Of course, they come in handy when you’re writing generic code (e.g. framework), but there is usually a better option in most cases.
You can find a lot of other verbs in the previous section.
