Here are some guidelines that will help you write better functions. If you follow them that is. Just reading doesn't guarantee anything. 😈
Responsibility
- A function should do only one thing and do it well ⭐ ⭐ ⭐
Naming your functions
- Write the usage first, define later.
- Verbs make better names than nouns.
- Take your time to name the function well. Especially the first time.
- Think about the order of your arguments
- Use interrogatives as prefixes when function answers a question.
is,does,has,areetc are all useful prefixes
Function length
- Try not to exceed a critical number of lines per function. I find 10 to be my limit. ⭐ ⭐ ⭐
- Do not "write now, refactor later".
- If a function is already written, ask yourself if you really need to add another line of code there.
Return values
- A function should always return something.
- If the function doesn't have anything meaningful to return, return a truthy/falsy value.
- Do not return inconsistent types.
- Do not return strings in a function that is supposed to return a number
Arguments
- Prioritise your most needed arguments to the left hand side.
- Optional arguments should always occur at the end of an argument list.
- Non-primitives are always passed by reference.