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/// Generate a range of integers from 0 to `element_num` (exclusive).
/// If `element_num` is negative, generate a range from 0 to `-element_num` (exclusive) with a step of -1.
///
/// # Arguments
/// * `element_num` - The number of elements in the range.
///
/// # Returns
/// * `Vec<i32>` - A vector containing the range of integers.
///
/// # Examples
/// ```rust
/// use lowdash::range;
/// let result = range(5);
/// assert_eq!(result, vec![0, 1, 2, 3, 4]);
/// ```
///
/// ```rust
/// use lowdash::range;
/// let result = range(-5);
/// assert_eq!(result, vec![0, -1, -2, -3, -4]);
/// ```
pub fn range(element_num: i32) -> Vec<i32> {
let length = if element_num < 0 {
-element_num
} else {
element_num
} as usize;
let step = if element_num < 0 { -1 } else { 1 };
let mut result = Vec::with_capacity(length);
for i in 0..length {
result.push((i as i32) * step);
}
result
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test_range_positive() {
let result = range(5);
assert_eq!(result, vec![0, 1, 2, 3, 4]);
}
#[test]
fn test_range_negative() {
let result = range(-5);
assert_eq!(result, vec![0, -1, -2, -3, -4]);
}
#[test]
fn test_range_zero() {
let result = range(0);
assert_eq!(result, Vec::<i32>::new());
}
}