CharlesO
How-To Exclude results from List Comprehensions
Say we have a simple list comprehensions:
for x <- [some_list] do
case _compute(x) do
nil -> nil # directly exclude this value from output
val -> val # add this value to output as usual
end
end
Short of running the whole comprehensions, the filtering out nil values,
is there a better was to do this?
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CharlesO
Got this elegant solution from StackOverflow:
for x <- list, y = _compute(x), do: y
I think the idea is if _compute(x) is truthy, return y, else if false / nil, it will be skipped, and you only have to evaluate _compute(x) once
Linuus
That’s a nice solution 
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