# ExConstructor

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ExConstructor is an Elixir library which makes it easy to instantiate
structs from external data, such as that emitted by a JSON parser.

ExConstructor provides a `define_constructor` macro which can be invoked
from a struct module.  The generated constructor, called `new` by default,
handles map-vs-keyword-list, string-vs-atom, and camelCase-vs-under_score
input data issues automatically, DRYing up your code and letting you
move on to the interesting parts of your program.

## Example

```elixir
defmodule TestStruct do
  defstruct field_one: nil,
            field_two: nil,
            field_three: nil,
            field_four: nil
  use ExConstructor
end

TestStruct.new(%{"field_one" => "a", "fieldTwo" => "b", :field_three => "c", :fieldFour => "d"})
# => %TestStruct{field_one: "a", field_two: "b", field_three: "c", field_four: "d"}
```

## [Full Documentation](http://hexdocs.pm/exconstructor/ExConstructor.html)

[Full ExConstructor documentation is available on
Hexdocs.pm.](http://hexdocs.pm/exconstructor/ExConstructor.html)


## Authorship and License

ExConstructor is copyright 2016 Appcues, Inc.

ExConstructor is released under the
[MIT License](https://github.com/appcues/exconstructor/blob/master/LICENSE.txt).