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pub struct StrRepeatArgs {
    pub str: &'static str,
    pub str_len: usize,
    pub out_len: usize,
    pub overflowed_len: Option<usize>,
    pub repeat: usize,
}

#[allow(non_snake_case)]
pub const fn StrRepeatArgs(str: &'static str, repeat: usize) -> StrRepeatArgs {
    let str_len = str.len();
    let (mul, overflowed) = str_len.overflowing_mul(repeat);

    let (out_len, overflowed_len, repeat) = if overflowed {
        (str_len, Some(mul), 1)
    } else {
        (mul, None, repeat)
    };

    StrRepeatArgs {
        str,
        str_len,
        out_len,
        overflowed_len,
        repeat,
    }
}

impl StrRepeatArgs {
    pub const fn assert_valid(&self) {
        if let Some(overflowed_len) = self.overflowed_len {
            [/* the returned string is too large */][overflowed_len]
        }
    }
}