Settings View Source Automatic Conversion of Middleman Projects

Run the following, indicating the directory containing your existing Middleman SLIM files, and a destination directory.

$ mix fermo.middleman_importer \
  --source middleman_project/source \
  --destination fermo_project/priv/source

Your .slim files will get copied and updated to make them work with Elixir SLIM.

About Elixir

TODO: LINK TO ELIXIR DOCS

data-structures

Data Structures

• Map is like Ruby's Hash,
• List is like Ruby's Array.

elixir-does-not-have-classes-and-objects

Elixir does not have classes and objects

There's no such thing as an instance of a class. Most of the time you work with functions, Maps and Lists.

elixir-does-not-have-mutable-data-structures

Elixir does not have mutable data structures

This means that you can't update things like Maps or Lists, you make modified copies.

elixir-is-a-compiled-language

Elixir is a compiled language

Before creating your Fermo pages, your project needs to be compiled. If there are errors in your SLIM templates, compilation will fail.

Fermo and SLIM

Fermo uses slime - a SLIM implementation in Elixir.

Compared to the Ruby implementation:

• each should be replaced by Enum.map,
• if and Enum.map should be preceded by = instead -,
• Partial parameters should be surrounded by %{} instead of {},
• Fermo passes two variables to SLIM templates: params and context, see the main README for info on these variables,
• In partials, locals: is not available, get values from params,
• The locale is included in the context as context.page.params.locale and cannot be obtained from I18n.locale,
• Use params.content in layouts instead of yield.

Adding Pages

In your config() method, you add single pages as follows:

config = page(
  config,
  "/templates/home_page.html.slim",
  "/index.html",
  %{page: page},
  %{}
)

For collections:

config = Enum.reduce(
  posts,
  config,
  fn post, config ->
    page(
      config,
      "/templates/post.html.slim",
      "/posts/#{post.slug}/index.html",
      %{post: post},
      %{}
    )
  end
)

Notes about Manual Conversions of Middleman to Fermo

• rename '.html' -> '.html.slim',
• convert old asset pipelines to Webpack,
• in layouts = yield -> = params.content,
• replace current_page.data.foo with params.foo.

handling-collections

Handling Collections

Create a block for each item in a list:

= Enum.map things, fn thing ->
  = thing.name

Include the list index:

= Enum.map Enum.with_index(things), fn {thing, i} ->
  = i
  = thing.name

Comparisons of SLIM and SLIME

partial

partial

head = partial "head", locals: {foo: true}

head = partial("partials/head", %{foo: true})

if

if

- if value
  It's true!

= if value do
  It's true!

if-else

if ... else

- if value
  It's true!
- else
  It's not true.

= if value do
  It's true!
- else
  It's not true.

ternary-if

Ternary if

- message = value ? "True" : "False"

- message = if value, do: "True", else: "False"

if-post-conditions

if post conditions

= squared_image(image: image, size: 70) if image.present?

= if image.present?
  = squared_image(image: image, size: 70)

escaped-and-unescaped-html

Escaped and unescaped HTML

In SLIM, == is used to introduce text that should not be HTML-escaped. This syntax has been introduced into SLIME, but requires a dependency on Phoenix's HTML engine (https://github.com/slime-lang/slime/pull/145). For now, this syntax is not supported by Fermo.

Libraries

Here are some example of replacements for common Ruby Gems used in Middleman projects:

• i18n - included in Fermo (see Fermo.i18n)

HOWTOs

debugging

Debugging

If you want to set a breakpoint for interactive debugging, start the build like this:

$ iex -S mix fermo.build

and put this where you want your beakpoint:

require IEx
IEx.pry()

rest-apis

REST APIs

If an API has a JSON Schema, use json_hyperschema_client_builder, which will generate a whole Elixir API library for you.

See this example, which generate a REST API client for DatoCMS.