Macro mapcomp::btreesetc

macro_rules! btreesetc {
    (@__ $acc:ident, $exp:expr; for $item:pat in $iter:expr; if $cond:expr) => { ... };
    (@__ $acc:ident, $exp:expr; for $item:pat in $iter:expr) => { ... };
    (@__ $acc:ident, $exp:expr; for $item:pat in $iter:expr; if $cond:expr; $($tail:tt)+) => { ... };
    (@__ $acc:ident, $exp:expr; for $item:pat in $iter:expr; $($tail:tt)+) => { ... };
    ($exp:expr; $($tail:tt)+) => { ... };
}

BTree Set Comprehension

Creates a BTreeSet from the contents of the comprehension. Same syntax as hashsetc!{}.

let pairs = btreesetc!{(i, j); for i in 4..7; for j in 10..12};

for i in 4..7 {
    for j in 10..12 {
        assert!(pairs.contains(&(i, j)));
    }
}