abetkin / shortdef

ShortDef

The library adds short syntax for maps as well as in-place guards definitions.

Basically, this allows you to write %{x} instead of %{x: x} and %MyStruct{x} instead of %MyStruct{x: x}.

defmodule S do
  defstruct [:x, :y]
  use ShortDef

  def f(%S{x, y: y}), do: {x, y}
end

Works only in function definitions, for globally-defined functions (with def).

You can also define guards inline:

defmodule M do
  use ShortDef

  # Equivalent to
  # def is_bounded(list, len) when is_list(list) and is_integer(len)
  def is_bounded(is_list(list), is_integer(len)) do
    length(list) < len
  end
end

Works only for guards, the builtin ones or defined with defguard.

You can combine these features too:

def f(%{is_integer(x)}) do

The library is 100% syntactic sugar with 0% semantics.

Similar libs

destructure

Installation

The package can be installed by adding shortdef to your list of dependencies in mix.exs:

def deps do
  [
    {:shortdef, "~> 0.1.0"}
  ]
end

Docs can be found at https://hexdocs.pm/shortdef.