#bool #conversion #convert #truthy

no-std eh

Convert values to bool, kind of like C, eh?

1 unstable release

0.1.0 Sep 19, 2019

#272 in No standard library

MIT/Apache

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eh

Latest Version docs

Convert values to bool, kind of like C, eh?

Eh roughly follows the implicit conversion rules for C to _Bool or C++ to bool, but Rust requires an explicit conversion. Integer 0, floating-point 0.0, and null pointers are false, and all other values are true.

As a Rust-specific extension, this is also implemented for Option<T> and Result<T, E>. It returns true when the ? operator would unwrap a T value, and false when ? would cause an early return.

Exclusions

Eh does not implement further boolean conversions of other languages, especially since they're not universal. For example:

  • JavaScript converts NaN to false, different than C and C++ (and eh).
  • JavaScript converts empty [] and {} to true, but in Python they're false.
  • Many languages convert empty strings to false and non-empty strings to true, but "0" is also false in Perl and PHP.

About

The name is a play on the Canadian "eh", turning a declarative sentence into a question.

License

This project is licensed under either of

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in eh by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.

No runtime deps