Class: Bmg::Operator::Autowrap

Inherits:
Object
  • Object
show all
Includes:
Unary
Defined in:
lib/bmg/operator/autowrap.rb

Overview

Autowrap operator.

Autowrap can be used to structure tuples ala Tutorial D’ wrap, but it works with conventions instead of explicit wrapping, and supports multiple levels or wrapping.

Examples:

[{ a: 1, b_x: 2, b_y: 3 }]     => [{ a: 1, b: { x: 2, y: 3 } }]
[{ a: 1, b_x_y: 2, b_x_z: 3 }] => [{ a: 1, b: { x: { y: 2, z: 3 } } }]

Autowrap supports the following options:

  • ‘postprocessor: :nil|:none|:delete|Hash|Proc` see NoLeftJoinNoise

  • ‘split: String` the seperator to use to split keys, defaults to `_`

Defined Under Namespace

Modules: Support Classes: NoLeftJoinNoise

Constant Summary collapse

DEFAULT_OPTIONS =
{
  :postprocessor => :none,
  :postprocessor_condition => :all,
  :split => "_"
}

Instance Attribute Summary

Attributes included from Bmg::Operator

#type

Class Method Summary collapse

Instance Method Summary collapse

Methods included from Unary

#bind

Methods included from Bmg::Operator

#inspect, #to_s

Methods included from Relation

#bind, #count, #debug, #delete, empty, #empty?, #insert, new, #one, #one_or_nil, #to_csv, #to_json, #to_xlsx, #type, #update, #visit, #with_type, #with_type_attrlist, #with_typecheck, #without_typecheck, #y_by_x, #ys_by_x

Methods included from Algebra

#allbut, #autosummarize, #autowrap, #constants, #extend, #group, #image, #join, #left_join, #matching, #materialize, #minus, #not_matching, #page, #project, #rename, #restrict, #spied, #summarize, #transform, #ungroup, #union, #unspied, #unwrap

Methods included from Algebra::Shortcuts

#cross_product, #exclude, #image, #images, #join, #left_join, #matching, #not_matching, #prefix, #rxmatch, #suffix, #ungroup, #unwrap, #where

Constructor Details

#initialize(type, operand, options = {}) ⇒ Autowrap

Returns a new instance of Autowrap.



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# File 'lib/bmg/operator/autowrap.rb', line 35

def initialize(type, operand, options = {})
  @type = type
  @operand = operand
  @original_options = options
  @options = normalize_options(options)
end

Class Method Details

.separator(options) ⇒ Object



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# File 'lib/bmg/operator/autowrap.rb', line 30

def separator(options)
  options[:split] || DEFAULT_OPTIONS[:split]
end

Instance Method Details

#_countObject



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# File 'lib/bmg/operator/autowrap.rb', line 65

def _count
  operand._count
end

#eachObject



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# File 'lib/bmg/operator/autowrap.rb', line 52

def each
  return to_enum unless block_given?
  @operand.each do |tuple|
    yield autowrap_tuple(tuple)
  end
end

#same_options?(opts) ⇒ Boolean

Returns:

  • (Boolean)


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# File 'lib/bmg/operator/autowrap.rb', line 48

def same_options?(opts)
  normalize_options(opts) == options
end

#to_astObject



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# File 'lib/bmg/operator/autowrap.rb', line 59

def to_ast
  [ :autowrap, operand.to_ast, @original_options.dup ]
end