Warning
This is work in progress and likely not maintained. It is mostly untested in real projects. It's here, so I can test it in real projects.
Axent contains some syntactic/grammatical extensions for Elixir. Opposed to
some other packages that provide similar functionality, this package actually
overrides core syntactic elements.
Axent is a personal experiment.
Axent is available on GitHub and can be installed
by adding axent to your list of dependencies in mix.exs:
def deps do
[
{:axent, github: "graupe/axent", runtime: false}
]
endAllow the use of with-style syntax on the top-level block of a function
definition.
defmodule SomeModule do
use Axent
def some_function(arg) do
{:ok, value} <- external_function(arg)
{:ok, value} <- more_function(value) \\ :morefu
value
else
{:morefu, {:error, reason}} -> {}
{:error, reason} -> {:error, reason}
end
endDefine a struct, and it's type in one go. This is similar to Algae
defdata but using
defstruct and none of the algebraic data type stuff. In addition, this code
is not tested thoroughly, yet. Also, the struct type is always t() without
any type arguments.
Notable is, that any field, that doesn't have a default value, will be part of
@enforce_keys. Defaults are denoted by a \\ at the end of a field definition.
defmodule SomeStruct do
use Axent
defstruct do
id :: non_neg_integer()
name :: binary() | nil \\ nil
end
endThese adaptations require that the AST (Abstract-Syntax-Tree) is rewritten,
before they are further evaluated by the Elixir compiler. The reason is, that
they change the grammar of Kernel.SpecialForm functions or macros.
This requires either wrapping the code in question with use Axent do :some_code end or enabling Axent in the outer scope, of the current block,
so that native language macros can be wrapped by Axent to do the rewrite on
the fly. (wrapped macros: defmodule/2, defprotocol/2, etc.)
Similar to the other short map packages, but rewriting the standard syntax. The variable pinning doesn't work anymore, in Elixir 1.8 and above.
use Axent do
aaa = 1
%{aaa: 1} = %{aaa}
%{aaa} = %{aaa: 2}
2 = aaa
# variable pinning broken
# %{^aaa} = %{aaa: ^aaa} = %{aaa: 1} = %{aaa}
endOr for implicit use within a module:
use Axent
defmodule SomeModule do
# use short maps here
end