kepik919
How to call "case/cond" over String.starts_with?(a)?
I want to call a normal function and do a pattern matching over it, such as:
res = String.starts_with?(a)
case res do
"a" -> # ....
"b" -> # ....
"c" -> # ....
"d" -> # ....
_ -> # .......
end
But this thing isn’t supported in Ellixir, is it? What’be be an alternative then?
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NobbZ
For this particular use case you can use regular pattern matching:
case a do
"a" <> _ -> # ...
end
hauleth
It is possible, just you use that function wrongly:
res = String.starts_with?(str, prefix)
case res do
true -> # …
false -> # …
end
APB9785
It looks like you want String.first/1:
case String.first(input) do
"a" -> # ....
"b" -> # ....
"c" -> # ....
"d" -> # ....
nil -> # input was an empty string
end
This type of case matching is totally acceptable (but hopefully you won’t make 27 different clauses for it!)
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