Class: LtdTemplate::Code::Subscript

Inherits:
LtdTemplate::Code show all
Defined in:
lib/ltdtemplate/code/subscript.rb

Instance Attribute Summary

Attributes inherited from LtdTemplate::Code

#tpl_methods

Instance Method Summary collapse

Methods inherited from LtdTemplate::Code

#do_method, #do_set, instance, #is_set?

Constructor Details

#initialize(template, base, subscripts) ⇒ Subscript

Returns a new instance of Subscript.



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# File 'lib/ltdtemplate/code/subscript.rb', line 12

def initialize (template, base, subscripts)
  super template
  @base, @subscripts = base, subscripts
end

Instance Method Details

#get_item(key) ⇒ Object 



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# File 'lib/ltdtemplate/code/subscript.rb', line 44

def get_item (key); target.get_item key; end

#get_value(opts = {}) ⇒ Object 



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# File 'lib/ltdtemplate/code/subscript.rb', line 74

def get_value (opts = {})
  case opts[:method]
  when '=' then do_set opts  # see LtdTemplate::Code
  else target.get_value opts
  end
end

#has_item?(key) ⇒ Boolean

Implement the subscript interface for the target.

Returns:

  • (Boolean) 


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# File 'lib/ltdtemplate/code/subscript.rb', line 43

def has_item? (key); target.has_item? key; end

#native_subs(usage = false) ⇒ Object

Return native subscripts calculated from the supplied code blocks.



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# File 'lib/ltdtemplate/code/subscript.rb', line 20

def native_subs (usage = false)
  nsubs = @subscripts ?
    @subscripts.map { |sub| sub.get_value.to_native }.flatten : []
  num_subs = nsubs.size
  if usage and num_subs > 0
 @template.using :subscript_depth, num_subs
 @template.use :subscripts, num_subs
  end
  nsubs
end

#set_item(key, value) ⇒ Object 



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# File 'lib/ltdtemplate/code/subscript.rb', line 45

def set_item (key, value); target(true).set_item key, value; end

#set_value(value) ⇒ Object

Set the target’s value.



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# File 'lib/ltdtemplate/code/subscript.rb', line 50

def set_value (value)
  subs = native_subs true
  if subs.size == 0
 # If there are no subscripts, just use the base.
 @base.set_value value
  else
 #
 # Traverse all but the last subscript, trying to autovivicate
 # new arrays as we go. This will silently fail if there is an
 # existing non-array value somewhere.
 #
 current = @base
 current.set_value @template.factory :array unless current.is_set?
 subs[0..-2].each do |sub|
    if !current.has_item? sub
  current.set_item sub, @template.factory(:array)
    end
    current = current.get_item sub
 end
 current.set_item subs[-1], value
  end
  self
end

#target(usage = false) ⇒ Object

Return the target value, variable[sub1, …, subN]



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# File 'lib/ltdtemplate/code/subscript.rb', line 34

def target (usage = false)
  current = @base.get_value
  native_subs(usage).each { |subs| current = current.get_item subs }
  current
end