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/// Removes the specified substring which first occurrence in the source string.
///
/// # Arguments
///
/// * `s` - The input string to perform remove.
/// * `substr` - The substring to be removed.
///
/// # Returns
///
/// Returns string after being removed.
///
/// # Examples
///
/// ```
/// use rufl::string;
///
/// let foo = string::remove_first("abca", "a");
/// assert_eq!("bca".to_string(), foo);
///
/// let bar = string::remove_first("abc", "d");
/// assert_eq!("abc".to_string(), bar);
///
///
/// ```
pub fn remove_first(s: impl AsRef<str>, substr: &str) -> String {
match s.as_ref().find(substr) {
Some(i) => s.as_ref()[0..i].to_string() + &s.as_ref()[i + substr.len()..].to_string(),
None => s.as_ref().to_string(),
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test_remove_first() {
assert_eq!("abc".to_string(), remove_first("abc", ""));
assert_eq!("bac".to_string(), remove_first("abac", "a"));
assert_eq!("abc".to_string(), remove_first("abc", "d"));
}
}