code: public function apply(Scope $scope, GenericList $arguments) {
  		foreach ($arguments as $pair) {
  			list($condition, $body) = $pair;
  			if ($condition->evaluate($scope)) return $body->evaluate($scope);
  		}
  	}
docs: Returns a value depending on a condition
  Usage: (cond ((is-integer? (%0)) 'Integer') ((is-string? (%0)) 'String') (true 'Unexpected type'))
  Returns: mixed
  (non-PHPdoc)
  @see \eMacros\Applicable::apply()