Class: Piglet::Relation::Foreach

Inherits:
Object
  • Object
show all
Includes:
Relation
Defined in:
lib/piglet/relation/foreach.rb

Overview

:nodoc:

Instance Attribute Summary

Attributes included from Relation

#sources

Instance Method Summary collapse

Methods included from Relation

#[], #alias, #cogroup, #cross, #distinct, #eql?, #field, #filter, #foreach, #group, #hash, #join, #limit, #method_missing, #order, #sample, #split, #stream, #union

Constructor Details

#initialize(relation, field_expressions) ⇒ Foreach

Returns a new instance of Foreach.



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# File 'lib/piglet/relation/foreach.rb', line 8

def initialize(relation, field_expressions)
  @sources, @field_expressions = [relation], [field_expressions].flatten
end

Dynamic Method Handling

This class handles dynamic methods through the method_missing method in the class Piglet::Relation::Relation

Instance Method Details

#schema ⇒ Object 



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# File 'lib/piglet/relation/foreach.rb', line 12

def schema
  description = @field_expressions.map { |expr| [expr.name, expr.type] }
  Piglet::Schema::Tuple.parse(description)
end

#to_s ⇒ Object 



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# File 'lib/piglet/relation/foreach.rb', line 17

def to_s
  "FOREACH #{@sources.first.alias} GENERATE #{field_expressions_string}"
end