/**
* 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;
}
/**
* @param ExpressionNode|NULL $node
* @return $this
*/
public function setValue($node)
{
if ($node === NULL) {
if (isset($this->value)) {
$this->value->previousUntil(Filter::isInstanceOf('\\Pharborist\\Variables\\VariableNode'))->remove();
$this->value->remove();
}
} else {
if (isset($this->value)) {
/** @var Node $node */
$this->value->replaceWith($node);
} else {
$this->append([Token::space(), Token::assign(), Token::space(), $node]);
}
}
return $this;
}