string_format/
lib.rs

1///Format the two strings together
2///  # Examples
3/// 
4/// ```
5/// extern crate string_format;
6/// use string_format::*;
7/// let hello = String::from("hello {}");
8/// let world = String::from("world");
9/// assert_eq!("hello world".to_string(), string_format(hello, world));
10/// ```
11pub fn string_format(string : String, text : String) -> String {
12    let mut result = string.clone();
13    //loop throught the String to find the first pair of brackets
14    match string.find("{}") {
15        Some(offset) => {
16            result.replace_range(offset..offset+2, &text);
17            result
18        }
19        None => { string }
20    }
21}
22
23///work like the format! macro but with a String
24/// # Example
25/// ```
26///  # #[macro_use] extern crate string_format;
27///  # fn main(){
28/// use string_format::*;
29/// 
30/// let hello = String::from("hello {} {}");
31/// let cruel = String::from("cruel");
32/// let world = String::from("world");
33/// assert_eq!("hello cruel world".to_string(), string_format!(hello, cruel, world));
34/// # }
35/// ```
36#[macro_export]
37macro_rules! string_format {
38    ($($arg:expr),*) => {{
39        let text = String::from("{}");
40        $(
41            let text = string_format(text, $arg);
42        )*
43        text
44    }}
45}
46
47#[cfg(test)]
48mod tests {
49    use super::*;
50
51    #[test]
52    fn test_string_format() {
53        assert_eq!("hello world".to_string(), string_format("hello {}".to_string(), "world".to_string()));
54    }
55
56    #[test]
57    fn test_string_format_macro(){
58        let hello = String::from("hello {} {}");
59        let cruel = String::from("cruel");
60        let world = String::from("world");
61        assert_eq!("hello cruel world".to_string(), string_format!(hello, cruel, world));
62    }
63}
string_format/lib.rs

string_format/
lib.rs
