Examine

Examine enhances Elixir IO.inspect debugging by displaying results alongside code and execution times.

Features

• Prints representation of expression passed as the first argument
• For pipelines, prints file code
• Prints results and execution times for each step in a pipeline
• Prints total execution time for a multi-step pipeline
• Prints filename and line number from where Examine.inspect/2 was called
• Option to print all the variables within the context where Examine.inspect/2 was called
• Optionally print a label at the top
• Global configuration and local options for colors and time units

The Examine.inspect/2 macro only affects the :dev environment by default and will compile to a noop in other environments. The affected environments can be changed via config, or per call via the :ignore_env option.

Documentation can be found at https://hexdocs.pm/examine.

Installation

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

def deps do
  [
    {:examine, "~> 0.2.0"}
  ]
end

Require the Examine module wherever you want to use it:

defmodule SomeModule
  require Examine

  def one_plus_two do
    Examine.inspect(1 + 2)
  end
end

Examples

Simple Usage

Examine.inspect(1 + 2)

Pipeline and Vars

list = [1, 2, 3]

list
|> Enum.map(&{&1, to_string(&1 * &1)})
|> Enum.into(%{})
|> Examine.inspect(show_vars: true)

Inspecting a Pipeline

list = [1, 2, 3]

list
|> Enum.map(&{&1, to_string(&1 * &1)})
|> Enum.into(%{})
|> Examine.inspect(inspect_pipeline: true, show_vars: true)

Inspecting a Pipeline with Anonymous Function

list = [1, 2, 3]

list
|> Enum.map(&{&1, to_string(&1 * &1)})
|> (fn val ->
      :timer.sleep(1000)
      val
    end).()
|> Enum.into(%{})
|> Examine.inspect(inspect_pipeline: true)

Setting Various Options

start = 1
increment = 1

start
|> Kernel.+(increment)
|> Kernel.+(increment)
|> Kernel.+(increment)
|> Kernel.+(increment)
|> Examine.inspect(
  inspect_pipeline: true,
  color: :yellow,
  bg_color: :blue,
  show_vars: true,
  time_unit: :nanosecond,
  label: "Setting A Lot of Options"
)

Acknowledgements

https://github.com/romul/dbg_inspect