Function column 

pub fn column<State: 'static>() -> FlexView<State>

An empty vertical flex, ready for fluent children (no any(..) wrapping).

use frust_widgets::{FlexView, column, text};
column()
    .child(text("a"))
    .flex(1, text("b"))
    .when(cond, |c| c.child(text("c")))