Module: Unsound::Control

Defined in:

lib/unsound/control.rb

Class Method Summary

• .maybe(&block) ⇒ Data::Nothing, Data::Just

  Execute the block.

• .try(&block) ⇒ Data::Right, Data::Left

  Try executing the block.

Class Method Details

.maybe(&block) ⇒ Data::Nothing, Data::Just

Execute the block. If the block results in Nil, return Data::Nothing, otherwise wrap the result in a Data::Just

Parameters:

• block (Block) —

  the block to execute

Returns:

• (Data::Nothing, Data::Just) —

  an instance of Data::Maybe

# File 'lib/unsound/control.rb', line 26

def maybe(&block)
  if (result = block.call).nil?
    Data::Nothing.new
  else
    Data::Just.new(result)
  end
end

.try(&block) ⇒ Data::Right, Data::Left

Try executing the block. If the block raises an exception wrap it in a Data::Left, otherwise wrap it in a Data::Right.

Parameters:

• block (Block) —

  the block to execute

Returns:

• (Data::Right, Data::Left) —

  an instance of a Data::Right or Data::Left to indicate success or failure.

# File 'lib/unsound/control.rb', line 14

def try(&block)
  Data::Right.new(block.call)
rescue
  Data::Left.new($ERROR_INFO)
end