How to query two components simultaneously?

[ArikRahman]

The tutorial shows how to query one component (the name):

fn greet_people(query: Query<&Name, &Age, With<Person>>) { for name in query.iter() { println!("hello {}!", name.0); } }

How do I query two components, say the age and the name of a person?

[rparrett]

Query takes two generic parameters, a query and a filter.

To query for multiple components or to query with multiple filters, you can use a tuple in either position.

fn greet_people(
    query: Query<(&Name, &Age), (With<Person>, With<SillyHat>)>
) {
    for (name, transform) in query.iter() {
        /* ... */
    }
}

[harudagondi]

fn greet_people(query: Query<(&Name, &Age), With<Person>>) {
	for (name, age) in query.iter() {
		println!("Hello {}! You are {} years old.", name.0, age.0); 
	} 
}

You use a tuple.

[ArikRahman]

Thanks guys, I played around with it and the tuple method worked!

[rparrett]

With<Person> is the filter part of the query and should be the second generic parameter of Query.

fn greet_people(
    query: Query<(&Name, &Gender), With<Person>>
) {
    for (name, gender) in query.iter() {
        /* ... */
    }
}