Skip to content

elixir/strain/1 #52

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
exercism-solutions-syncer wants to merge 1 commit into
base: main
Choose a base branch
from
+27 −0
Open

elixir/strain/1 #52

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
27 changes: 27 additions & 0 deletions solutions/elixir/strain/1/lib/strain.ex
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,27 @@
defmodule Strain do
@doc """
Given a `list` of items and a function `fun`, return the list of items where
`fun` returns true.

Do not use `Enum.filter`.
"""
@spec keep(list :: list(any), fun :: (any -> boolean)) :: list(any)
def keep(list, fun) do
list
|> Enum.reduce([], &if(fun.(&1), do: [&1 | &2], else: &2))
|> Enum.reverse()
end

@doc """
Given a `list` of items and a function `fun`, return the list of items where
`fun` returns false.

Do not use `Enum.reject`.
"""
@spec discard(list :: list(any), fun :: (any -> boolean)) :: list(any)
def discard(list, fun) do
list
|> Enum.reduce([], &if(fun.(&1), do: &2, else: [&1 | &2]))
|> Enum.reverse()
end
end