vendor/typenum/README.md

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   3
   4 Typenum
   5 =====
   6
   7 Typenum is a Rust library for type-level numbers evaluated at compile time. It currently
   8 supports bits, unsigned integers, and signed integers.
   9
  10 Typenum depends only on libcore, and so is suitable for use on any platform!
  11
  12 For the full documentation, go [here](https://docs.rs/typenum).
  13
  14 ### Importing
  15
  16 While `typenum` is divided into several modules, they are all re-exported through the crate root,
  17 so you can import anything contained herein with `use typenum::whatever;`, ignoring the
  18 crate structure.
  19
  20 You may also find it useful to treat the `consts` module as a prelude, perfoming a glob import.
  21
  22 ### Example
  23
  24 Here is a trivial example of `typenum`'s use:
  25
  26 ```rust
  27 use typenum::{Sum, Exp, Integer, N2, P3, P4};
  28
  29 type X = Sum<P3, P4>;
  30 assert_eq!(<X as Integer>::to_i32(), 7);
  31
  32 type Y = Exp<N2, P3>;
  33 assert_eq!(<Y as Integer>::to_i32(), -8);
  34 ```
  35
  36 For a non-trivial example of its use, see one of the crates that depends on it. The full
  37 list is [here](https://crates.io/crates/typenum/reverse_dependencies). Of note are
  38 [dimensioned](https://crates.io/crates/dimensioned/) which does compile-time type
  39 checking for arbitrary unit systems and
  40 [generic-array](https://crates.io/crates/generic-array/) which provides arrays whose
  41 length you can generically refer to.
  42
  43 ### Error messages
  44
  45
  46 Typenum's error messages aren't great, and can be difficult to parse. The good news is
  47 that the fine folks at Auxon have written a tool to help with it. Please take a look at
  48 [tnfilt](https://github.com/auxoncorp/tnfilt).
  49