class Sass::Script::Tree::Operation
A SassScript parse node representing a binary operation, such as `$a + $b` or `“foo” + 1`.
Attributes
Public Class Methods
@param operand1 [Sass::Script::Tree::Node] The parse-tree node
for the right-hand side of the operator
@param operand2 [Sass::Script::Tree::Node] The parse-tree node
for the left-hand side of the operator
@param operator [Symbol] The operator to perform.
This should be one of the binary operator names in {Sass::Script::Lexer::OPERATORS}
# File lib/sass/script/tree/operation.rb, line 15 def initialize(operand1, operand2, operator) @operand1 = operand1 @operand2 = operand2 @operator = operator super() end
Public Instance Methods
Returns the operands for this operation.
@return [Array<Node>] @see Sass::Script::Tree::Node#children
# File lib/sass/script/tree/operation.rb, line 44 def children [@operand1, @operand2] end
@see Sass::Script::Tree::Node#deep_copy
# File lib/sass/script/tree/operation.rb, line 49 def deep_copy node = dup node.instance_variable_set('@operand1', @operand1.deep_copy) node.instance_variable_set('@operand2', @operand2.deep_copy) node end
@return [String] A human-readable s-expression representation of the operation
# File lib/sass/script/tree/operation.rb, line 23 def inspect "(#{@operator.inspect} #{@operand1.inspect} #{@operand2.inspect})" end
@see Sass::Script::Tree::Node#to_sass
# File lib/sass/script/tree/operation.rb, line 28 def to_sass(opts = {}) o1 = operand_to_sass @operand1, :left, opts o2 = operand_to_sass @operand2, :right, opts sep = case @operator when :comma; ", " when :space; " " else; " #{Sass::Script::Lexer::OPERATORS_REVERSE[@operator]} " end "#{o1}#{sep}#{o2}" end
Protected Instance Methods
Evaluates the operation.
@param environment [Sass::Environment] The environment in which to evaluate the SassScript @return [Sass::Script::Value] The SassScript object that is the value of the operation @raise [Sass::SyntaxError] if the operation is undefined for the operands
# File lib/sass/script/tree/operation.rb, line 63 def _perform(environment) value1 = @operand1.perform(environment) # Special-case :and and :or to support short-circuiting. if @operator == :and return value1.to_bool ? @operand2.perform(environment) : value1 elsif @operator == :or return value1.to_bool ? value1 : @operand2.perform(environment) end value2 = @operand2.perform(environment) if (value1.is_a?(Sass::Script::Value::Null) || value2.is_a?(Sass::Script::Value::Null)) && @operator != :eq && @operator != :neq raise Sass::SyntaxError.new( "Invalid null operation: \"#{value1.inspect} #{@operator} #{value2.inspect}\".") end begin result = opts(value1.send(@operator, value2)) rescue NoMethodError => e raise e unless e.name.to_s == @operator.to_s raise Sass::SyntaxError.new("Undefined operation: \"#{value1} #{@operator} #{value2}\".") end if (@operator == :eq || @operator == :neq) && value1.is_a?(Sass::Script::Value::Number) && value2.is_a?(Sass::Script::Value::Number) && value1.unitless? != value2.unitless? && result == (if @operator == :eq Sass::Script::Value::Bool::TRUE else Sass::Script::Value::Bool::FALSE end) operation = "#{value1} #{@operator == :eq ? '==' : '!='} #{value2}" future_value = @operator == :neq Sass::Util.sass_warn <<WARNING DEPRECATION WARNING on line #{line}#{" of #{filename}" if filename}: The result of `#{operation}` will be `#{future_value}` in future releases of Sass. Unitless numbers will no longer be equal to the same numbers with units. WARNING end result end
Private Instance Methods
# File lib/sass/script/tree/operation.rb, line 110 def operand_to_sass(op, side, opts) return "(#{op.to_sass(opts)})" if op.is_a?(Sass::Script::Tree::ListLiteral) return op.to_sass(opts) unless op.is_a?(Operation) pred = Sass::Script::Parser.precedence_of(@operator) sub_pred = Sass::Script::Parser.precedence_of(op.operator) assoc = Sass::Script::Parser.associative?(@operator) return "(#{op.to_sass(opts)})" if sub_pred < pred || (side == :right && sub_pred == pred && !assoc) op.to_sass(opts) end