Function write_if_else 

pub(crate) fn write_if_else(
    output: &mut (impl Write + ?Sized),
    pred: bool,
    true_bytes: &[u8],
    false_bytes: &[u8],
) -> Result<usize>

Available on crate feature formatting only.

If pred is true, write true_bytes to the output. Otherwise, write false_bytes.