phpify/string/
lcfirst.rs

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17
18/// Make a string's first character lowercase
19///
20/// # Description
21///
22/// Returns a string with the first character of str lowercased if that character is alphabetic.
23///
24/// Note that 'alphabetic' is determined by the current locale. For instance, in the default "C"
25/// locale characters such as umlaut-a (ä) will not be converted.
26///
27/// # Examples
28///
29/// Example #1 lcfirst() example
30///
31/// ```
32/// use phpify::string::lcfirst;
33///
34/// let foo = "HelloWorld";
35/// assert_eq!(lcfirst(foo), "helloWorld");
36///
37/// let bar = "HELLO WORLD!";
38/// assert_eq!(lcfirst(bar), "hELLO WORLD!");
39/// ```
40pub fn lcfirst<S>(str: S) -> String
41    where
42        S: AsRef<str> {
43
44    let mut chars = str.as_ref().chars();
45
46    match chars.next() {
47        None => String::new(),
48        Some(char) => char.to_lowercase().collect::<String>() + chars.as_str(),
49    }
50}
51
52#[cfg(test)]
53mod tests {
54    use crate::string::lcfirst;
55
56    #[test]
57    fn test() {
58        assert_eq!(lcfirst("ABC"), "aBC");
59        assert_eq!(lcfirst("ÄBC"), "äBC");
60        assert_eq!(lcfirst("ΔΞΠ"), "δΞΠ");
61    }
62}
phpify/string/lcfirst.rs

phpify/string/
lcfirst.rs
