fn addExtra(i: *Interner, gpa: Allocator, extra: anytype) Allocator.Error!u32
fn addExtra(i: *Interner, gpa: Allocator, extra: anytype) Allocator.Error!u32 { const field_count = @typeInfo(@TypeOf(extra)).@"struct".field_names.len; try i.extra.ensureUnusedCapacity(gpa, field_count); return i.addExtraAssumeCapacity(extra); }