Credo
Credo v1.6.4

View Source Credo.Check.Design.AliasUsage (Credo v1.6.4)

This check has a base priority of normal and works with any version of Elixir.

Explanation

Functions from other modules should be used via an alias if the module's namespace is not top-level.

While this is completely fine:

defmodule MyApp.Web.Search do
  def twitter_mentions do
    MyApp.External.TwitterAPI.search(...)
  end
end

... you might want to refactor it to look like this:

defmodule MyApp.Web.Search do
  alias MyApp.External.TwitterAPI

  def twitter_mentions do
    TwitterAPI.search(...)
  end
end

The thinking behind this is that you can see the dependencies of your module at a glance. So if you are attempting to build a medium to large project, this can help you to get your boundaries/layers/contracts right.

As always: This is just a suggestion. Check the configuration options for tweaking or disabling this check.

Check-Specific Parameters

Use the following parameters to configure this check:

:excluded_namespaces

List of namespaces to be excluded for this check.

This parameter defaults to ["File", "IO", "Inspect", "Kernel", "Macro", "Supervisor", "Task", "Version"].

:excluded_lastnames

List of lastnames to be excluded for this check.

This parameter defaults to ["Access", "Agent", "Application", "Atom", "Base", "Behaviour", "Bitwise", "Code", "Date", "DateTime", "Dict", "Enum", "Exception", "File", "Float", "GenEvent", "GenServer", "HashDict", "HashSet", "Integer", "IO", "Kernel", "Keyword", "List", "Macro", "Map", "MapSet", "Module", "NaiveDateTime", "Node", "OptionParser", "Path", "Port", "Process", "Protocol", "Range", "Record", "Regex", "Registry", "Set", "Stream", "String", "StringIO", "Supervisor", "System", "Task", "Time", "Tuple", "URI", "Version"].

:if_nested_deeper_than

Only raise an issue if a module is nested deeper than this.

This parameter defaults to 0.

:if_called_more_often_than

Only raise an issue if a module is called more often than this.

This parameter defaults to 0.

:only

Regex or a list of regexes that specifies which modules to include for this check.

excluded_namespaces and excluded_lastnames take precedence over this parameter.

This parameter defaults to nil.

General Parameters

Like with all checks, general params can be applied.

Parameters can be configured via the .credo.exs config file.