Class: Array

Inherits:
Object
  • Object
show all
Defined in:
lib/cascading/ext/array.rb

Overview

Extensions to Arrays in support of variable length lists of field names. This is not pretty, but supports DSL features like:

group_by 'field1', 'field2', :sort_by => 'field3' do
  ...
end

The most obvious limitation of the approach is that function definitions of the form f(*args_with_options) are not self-documenting. To compensate for this, documentation of all arguments and optional parameters must be provided on the DSL method.

Instance Method Summary collapse

Instance Method Details

#extract_options ⇒ Object

Non-destructive form of Array#extract_options!



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# File 'lib/cascading/ext/array.rb', line 23

def extract_options
   last.is_a?(::Hash) ? last : {}
end

#extract_options! ⇒ Object

Use this extension to extract the optional parameters from a *args_with_options argument. So if you have a function:

def f(*args_with_options)

You can destructively process the args_with_options as follows:

options, just_args = args_with_options.extract_options!, args_with_options



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# File 'lib/cascading/ext/array.rb', line 18

def extract_options!
   last.is_a?(::Hash) ? pop : {}
end