structural 0.4.3

// This module is not being used for anything right now,
// because expressions other than string literals can't reliably be used
// as a `&'static str` const parameter yet
// (they cause compiler errors depending on the nightly version).
//
//
// Helpers for operating on a `&str` const parameter,
// when `TStr` internally uses a `&'static str` const parameter instead of
// a tuple of char type-level characters(a bunch of structs).

/// For converting a `ts!(99)` to a 99 constant,for example.
pub(crate) const fn str_to_usize(s: &str) -> usize {
    const fn inner(s: &[u8], index: usize, curr: usize) -> usize {
        if index < s.len() {
            let digit = (s[index] - b'0') as usize;
            // This has the effect of panicking on non to '0' to '9' characters.
            #[allow(clippy::no_effect)]
            {
                [(); 10][9 - digit];
            }
            inner(s, index + 1, (curr * 10) + digit)
        } else {
            curr
        }
    }
    inner(s.as_bytes(), 0, 0)
}

pub struct StrFromLiteral<T> {
    pub literal: T,
    pub stringified: &'static str,
}

impl<T> StrFromLiteral<T> {
    pub const fn new(literal: T, stringified: &'static str) -> Self {
        Self {
            literal,
            stringified,
        }
    }
}

impl StrFromLiteral<&'static str> {
    pub const fn str_from_lit(self) -> &'static str {
        self.literal
    }
}

impl StrFromLiteral<u128> {
    pub const fn str_from_lit(self) -> &'static str {
        self.stringified
    }
}