我想替换内部match语句并为字母表用尽时的所有值工作.我知道我可以自己写,但我想使用内置函数.
fn convert(inp: u32, out: u32, numb: &String) -> Result<String, String> {
match isize::from_str_radix(numb, inp) {
Ok(a) => match out {
2 => Ok(format!("{:b}", a)),
8 => Ok(format!("{:o}", a)),
16 => Ok(format!("{:x}", a)),
10 => Ok(format!("{}", a)),
0 | 1 => Err(format!("No base lower than 2!")),
_ => Err(format!("printing in this base is not supported")),
},
Err(e) => Err(format!(
"Could not convert {} to a number in base {}.\n{:?}\n",
numb, inp, e
)),
}
}
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