Symfony 4 event listener not registering56

What are the seven data types?56

• number for both floating-point and integer numbers


• String for strings,


• boolean for logical values: true/false,


• null – a type with a single value null, meaning “empty” or “does not exist”, undefined – a type with a single value


• object and symbol – for complex data structures and unique identifiers, we haven’t learnt them yet.


• null – a type with a single value null, meaning “empty” or “does not exist”, undefined – a type with a single value


• number for both floating-point and integer numbers