How to use the gonzales-pe/lib/node/node-types.MixinType function in gonzales-pe

* Node type definitions.
 * This duplicated Gonzales mapping to allow easier updates,
 * should the Gonzales source naming system ever change.
 */
var NodeType = {
  ARGUMENTS:      GonzalesNodeType.ArgumentsType,
  AT_RULE:        GonzalesNodeType.AtrulerType,
  COMMENT:        GonzalesNodeType.CommentSLType,
  DECLARATION:    GonzalesNodeType.DeclarationType,
  EXTEND:         GonzalesNodeType.ExtendType,
  FUNCTION:       GonzalesNodeType.FunctionType,
  IDENTIFIER:     GonzalesNodeType.IdentType,
  INCLUDE:        GonzalesNodeType.IncludeType,
  INTERPOLATION:  GonzalesNodeType.InterpolationType,
  LOOP:           GonzalesNodeType.LoopType,
  MIXIN:          GonzalesNodeType.MixinType,
  OPERATOR:       /operator/i,
  PARENTHESIS:    GonzalesNodeType.ParenthesesType,
  PROPERTY:       GonzalesNodeType.PropertyType,
  RULESET:        GonzalesNodeType.RulesetType,
  SELECTOR:       GonzalesNodeType.SimpleselectorType,
  STYLE_SHEET:    GonzalesNodeType.StylesheetType,
  VALUE:          GonzalesNodeType.ValueType,
  VARIABLE:       GonzalesNodeType.VariableType
};

/**
 * Removable node types.
 * (compiled to a keyed hash for direct lookup access)
 */
var RemovableTypes = [
  NodeType.DECLARATION,