Method: Less::Node::Expression#evaluate

Defined in:
lib/less/engine/nodes/property.rb

#evaluate(env = nil) ⇒ Object

Evaluates the expression and instantiates a new Literal with the result ex: [#111, +, #111] will evaluate to a Color node, with value #222



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# File 'lib/less/engine/nodes/property.rb', line 188

def evaluate env = nil
#        puts "expression #{self.inspect} env: #{env ? env.variables : "nil"}"
  if size > 2 or !terminal?
#          puts " SIZE > 2 or !terminal"

#          puts "--- sub evaluation ---"

    # Replace self with an evaluated sub-expression
    evaled = self.class.new(map {|e| e.respond_to?(:evaluate) ? e.evaluate(env) : e }, parent, delimiter) #5

#          puts "======================"
#          puts "evaled => #{evaled.inspect}"

    unit = evaled.literals.map do |node|
      node.unit
    end.compact.uniq.tap do |ary|
      raise MixedUnitsError, evaled * ' ' if ary.size > 1 && !evaled.operators.empty?
    end.join

    entity = evaled.literals.find {|e| e.unit == unit } || evaled.literals.first || evaled.entities.first
    result = evaled.operators.empty?? evaled : eval(evaled.to_ruby.join)

#          puts "entity is a #{entity.class}"
#          puts "delimiter is |#{@delimiter}|"

    case result
      when Entity     then result
      when Expression then result.one?? result.first : self.class.new(result, parent, delimiter)
      else entity.class.new(result, *(unit if entity.class == Node::Number))
    end
  elsif size == 1
    if first.is_a? Variable
      first.evaluate(env)
    elsif first.is_a? Function
      first.evaluate(env)
    else
      first
    end
  else
    self
  end
end