pub fn fallible_position<T, E>(
iter: impl IntoIterator<Item = T>,
predicate: impl FnMut(T) -> Result<bool, E>,
) -> Result<Option<usize>, E>Expand description
Returns Ok(Some(index)) for the first element where the predicate returns
Ok(true), Ok(None) if no element satisfies it, or Err on the first
error.