Struct ParamSet 

pub struct ParamSet<T> { /* private fields */ }

A parameter that allows disjoint access to multiple queries with conflicting access.

Normally, two queries that access the same component cannot be used together because of Rust’s aliasing rules. ParamSet solves this by ensuring only one query can be accessed at a time.

Example

// Future: When Query is implemented
fn conflicting_access(
    // These would conflict: both access Position
    // query1: Query<&mut Position>,
    // query2: Query<&Position, With<Player>>,

    // Solution: use ParamSet
    mut set: ParamSet<(Query<&mut Position>, Query<&Position, With<Player>>)>,
) {
    // Access one at a time
    for pos in set.p0().iter_mut() {
        pos.x += 1.0;
    }
    // p0 is dropped before p1 is accessed
    for pos in set.p1().iter() {
        println!("Player position: {:?}", pos);
    }
}

Note

This is a placeholder for the full ParamSet implementation, which requires Query to be implemented first (Step 3.1.3).

Trait Implementations

impl<T: Debug> Debug for ParamSet<T>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.