# Cartograf
[](https://travis-ci.org/Herlitzd/cartograf)
## Struct-to-Struct Mapping Utility for Elixir
*This Project is still under development, and may not be safe for production.*
Documentation can be found at [https://hexdocs.pm/cartograf](https://hexdocs.pm/cartograf).
### Building Mapping Functions
```elixir
defmodule A, do: defstruct [:a, :b, :cc, :d]
defmodule B, do: defstruct [:a, :b, :c, :d, :e]
defmodule YourModule do
use Cartograf
map A, B, :a_to_b do
[
# No need to directly map identical keys, i.e.
# let(:a, :a)
let(:cc, :c)
]
end
# auto mapping can be turned off
map A, B, :a_to_b, auto: false do
...
end
map B, A, :b_to_a do
[
# Keys that shouldn't be mapped can be dropped
drop(:e)
]
end
end
```
### Invoking Mapping Functions
```elixir
iex> YourModule.a_to_b(%A{a: 1, b: 2, c: 3, d: 4})
%B{a: 1, b: 2, c: 3, d: 4, e: nil}
```
## List of Forms
For more information, please look at the docs and tests.
* `map(from_module, to_module, name_of_fn, opts) do ...`\
Setup a new mapping function
* `let(from_symbol, to_symbol)`\
Set field to field mapping
* `drop(from_symbol)`\
Prevent a source field from being mapped
* `const(to_symbol, value)`\
Provide a constant value for a destination field
* `nest(nested_module, dest_key) do ...`\
Specify a nested struct type, and a destination field for it.
## Installation
The package can be installed
by adding `cartograf` to your list of dependencies in `mix.exs`:
```elixir
def deps do
[
{:cartograf, "~> 0.1.0"}
# or
{:cartograf, git: "https://github.com/Herlitzd/cartograf.git"}
]
end
```
