Function array_lower

src/expr/src/scalar/func.rs:2743–2757

(a: Array<'a>, i: i64)

// TODO(benesch): remove potentially dangerous usage of `as`.
#[allow(clippy::as_conversions)]
fn array_lower<'a>(a: Array<'a>, i: i64) -> Result<Option<i32>, EvalError> {
    if i < 1 {
        return Ok(None);
    }
    a.dims()
        .into_iter()
        .nth(i as usize - 1)
        .map(|dim| {
            let (lower, _upper) = dim.dimension_bounds();
            lower
                .try_into()
                .map_err(|_| EvalError::Int32OutOfRange(lower.to_string().into()))
        })
        .transpose()
}

#[sqlfunc(
    output_type_expr = "input_types[0].scalar_type.without_modifiers().nullable(true)",