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vic/happy_with

Avoid commas on Elixir's with special form.

vic/happy_with.json
{
"defaultBranch": "master",
"description": "Avoid commas on Elixir's with special form.",
"fullName": "vic/happy_with",
"homepage": "",
"language": "Elixir",
"name": "happy_with",
"pushedAt": "2025-07-15T04:33:39Z",
"stargazersCount": 31,
"updatedAt": "2025-07-15T04:33:42Z",
"url": "https://github.com/vic/happy_with"
}

Travis Hex.pm

Tiny syntax sugar around Elixir’s with special form.

Because I’m happy on how Elixir’s with special form works, and can get used to the <- arrow but I still dont like to place commas between all the with expressions.

Back then before elixir 1.2 release, I implemented happy using case expressions, it leaked variables as normal case expressions would do, and overriding the standard = operator turned out to have some unexpected issues. Also, after using standard with a bit, I really got to like it, except for the fact of having to place commas after expressions, so I wrote happy_with which is a very tiny macro that just rewrites to Elixir’s standard with special form.

This package implements the tags feature originally found in happy_path.

For more examples see docs

Available in Hex, the package can be installed as:

  1. Add happy_with to your list of dependencies in mix.exs:
def deps do
[{:happy_with, "~> 1.0"}]
end
import HappyWith
happy_with do
{:ok, friend} <- retrieve_friend
String.downcase(friend)
else
_ -> "nobody"
end

rewrites into standard with form. Only the last expression in the happy_with block is given to with’s do.

with({:ok, friend} <- retrieve_friend)
do
name = String.downcase(friend)
else
_ -> "nobody"
end

IMHO the first one reads better.

Rewrites the given block and else clauses into Elixir’s standard with form.

iex> import HappyWith
iex> happy_with do
...> {:ok, name} <- {:ok, "joSE"}
...> lower = String.downcase(name)
...> lower
...> end
"jose"

You can also provide else clauses to the with form.

iex> import HappyWith
iex> happy_with do
...> {:ok, name} <- {:error, :nobody}
...> _never_reached = String.downcase(name)
...> else
...> {:error, _} -> "luis"
...> end
"luis"

You can also use tags a feature from the happy project.

iex> import HappyWith
iex> happy_with do
...> @something {:ok, name} when is_binary(name) and length(name) > 3 <- {:error, :nobody}
...> _never_reached = String.downcase(name)
...> else
...> {:something, {:error, _}} -> "could not fetch name"
...> end
"could not fetch name"