Establishing Guidelines for Maximizing Anonymous Function Readability in Reference to Escaped and Expanded Notations about elixir_style_guide

[christopheradams]

"Readability" can be subjective. Can you think of some examples that would illustrate the guideline? Also, I'd probably phrase this in terms of anonymous functions rather than lambdas, to keep it in line with the official docs.

If the position of the elements or operations in the anonymous function define the variables, then I would say an expanded anonymous function is redundant. For example,

f = &(&1 + 1)
# and 
g = &([&2 | &1])

are both defined wholly by their form, without variable names. You can look at each of these and see that f is an increment function and g is a reversal function. Especially if you're piping into them.

[christopheradams]

I think we can state a preference for using the capture operator when defining an anonymous function for a known function and arity.

However, in the case of using the capture operator for partially applied functions with placeholder values, I'm not confident there could be a hard and fast rule for when variable names are "essential for readability".

I understand your point that anonymous functions that use simple operators or list operations don't need to be written out fully using fn... end. If you can write up a style rule that expresses it, I would consider it.