/**
* Creates a negated version of any expression. For instance, passing a
* VariableNode will result in !$var.
*
* @param \Pharborist\ExpressionNode $expr
* The expression to negate.
*
* @return static
*/
public static function fromExpression(ExpressionNode $expr)
{
$not = new static();
$not->addChild(Token::not(), 'operator');
/** @var \Pharborist\Node $expr */
$not->addChild($expr->remove(), 'operand');
return $not;
}
