/**
* Node factory, creating an appropriate Node from a Token.
*
* Based on the provided Token, returns a TerminalNode if the
* token type is PosInt, Integer, RealNumber, Identifier or Constant
* otherwise returns null.
*
* @param Token $token Provided token
* @retval Node|null
*/
public static function factory(Token $token)
{
switch ($token->getType()) {
case TokenType::PosInt:
case TokenType::Integer:
$x = intval($token->getValue());
return new NumberNode($x);
case TokenType::RealNumber:
$x = floatval($token->getValue());
return new NumberNode($x);
case TokenType::Identifier:
return new VariableNode($token->getValue());
case TokenType::Constant:
return new ConstantNode($token->getValue());
case TokenType::FunctionName:
return new FunctionNode($token->getValue(), null);
case TokenType::OpenParenthesis:
return new SubExpressionNode($token->getValue());
case TokenType::AdditionOperator:
case TokenType::SubtractionOperator:
case TokenType::MultiplicationOperator:
case TokenType::DivisionOperator:
case TokenType::ExponentiationOperator:
return new ExpressionNode(null, $token->getValue(), null);
default:
// echo "Node factory returning null on $token\n";
return null;
}
}
private function assertTokenEquals($value, $type, Token $token)
{
$this->assertEquals($value, $token->getValue());
$this->assertEquals($type, $token->getType());
}