Ehelper

** Provides a command "e" for accessing external documentation from the Iex shell**

Motivation

Eventually in any Elixir project you will need to access some Erlang apis. This project started as way to extend the h command in iex to access documentation on Erlang functions from the man pages installed on with Erlang on most unix installations. It has grown since then as a way to provide a dynamic backend to internal documentation within iex.

Documentation

The Ehelper defines a behaviour and plugin scheme that can access documentation in many different ways. Currently it comes with helpers that can open the documentation for functions in either Dash, a web browser or provide inline documentation for Erlang functions.

Examples

iex> import Ehelper
iex> e Atom
                                  Atom
Convenience functions for working with atoms.
See also Kernel.is_atom/1.

iex> Ehelper.Config.configure(doc_helpers: [helpers: [Ehelper.DocHelp.Elixir, Ehelper.DocHelp.Erlman]])
iex>  e :crypto.stop
                          :crypto.stop()
stop() -> ok
Equivalent to application:stop(crypto).

iex> Ehelper.Config.configure(doc_helpers: [helpers: [Ehelper.DocHelp.Elixir, Ehelper.DocHelp.PrintUrl]])
iex(13)> e :erlang.xor/1

                                :erlang

Documentation can be found at http://www.erlang.org/doc/man/erlang.html#xor-1

Note: The Erlman man page parser is still a work in progress and still has many edge cases to work through. If you are using the Erlman helper and get No documentation found, do not take that as gospel.

Using Ehelper

The current list of DocHelpers:

Ehelper.DocHelp.Elixir
- Duplicates current h command for Elixir modules.
Ehelper.DocHelp.Erlman
- Duplicate h command for Erlang functions by parsing man pages.
Ehelper.DocHelp.PrintUrl
- Print a url for either Elixir or Erlang functions, is hex aware, but assumes all Erlang functions are at erlang.org.
Ehelper.DocHelp.OpenUrl
- Calls system open on the output of PrintUrl, only tested on OS X.
Ehelper.DocHelp.DashDoc
- Open Dash to documentation for function, has some support for hex.pm downloads.

The current default helpers are [Ehelper.DocHelp.Elixir, Ehelper.DocHelp.PrintUrl] In order to use Ehelper from within iex, you must start iex with the location of all the Ehelper BEAM files in it's code path. You can then use import Ehelper at the iex prompt or in your .iex files.

TODO

Document all the Helpers
Automate the install procedure
Fix Erlman Edge cases
Figure out how to open URL's on Windows and Linux.

Installation

There is a simple install script install.sh that will install the compiled BEAM files into ~/.iex/ebin and a sample.iex.exs file that configures the e command to use Erlang man pages. You will need to either call iex with the --pa or --pz options or env ERL_LIBS=~/.iex iex.

If available in Hex, the package can be installed as:

Add ehelper to your list of dependencies in mix.exs:

```elixir
def deps do
  [{:ehelper, "~> 0.1.0"}]
end
```

Ensure ehelper is started before your application:

```elixir
def application do
  [applications: [:ehelper]]
end
```

philosophers-stone / ehelper