fn has_seen(var: VarId, seen: Option<&Seen<'_>>) -> bool {
    let mut next = seen;
    while let Some(node) = next {
        if node.var == var {
            return true;
        }
        next = node.next;
    }
    false
}
/// Whether the linked list contains that var
Whether the linked list contains that var
Whether the linked list contains that var
fn has_seen(var: VarId, seen: Option<&Seen<'_>>) -> bool {
    let mut next = seen;
    while let Some(node) = next {
        if node.var == var {
            return true;
        }
        next = node.next;
    }
    false
}
fn has_seen ( var : VarId , seen : Option < & Seen < ' _ > > ) -> bool { let mut next = seen ; while let Some ( node ) = next { if node . var == var { return true ; } next = node . next ; } false }
Whether the linked list contains that var
Whether the linked list contains that var
var
VarId
seen
Option<&Seen<'_>>
var
VarId
seen
Option<&Seen<'_>>