Using version `1.0.0`, without default features, fails with compile error [edited: not an issue]

[cipriancraciun]

[Not sure if this is an issue indeed, or a small "feature request".]

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As the subject says, trying to use the regex crate version 1.0.0, without the default features, and with the latest nightly (2018-05-18) fails with the following compile time error:

error[E0432]: unresolved import `Error`
  --> /home/ciprian/.cargo/registry/src/github.com-1ecc6299db9ec823/regex-1.0.0/src/compile.rs:25:5
   |
25 | use Error;
   |     ^^^^^ no `Error` in the root. Did you mean to use `error`?

error: aborting due to previous error

For more information about this error, try `rustc --explain E0432`.

The way I include the dependency is:

[dependencies.regex]
version = "~1.0.0"
optional = true
features = []
default-features = false

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It seems that with the default-features = true and without any additional features enabled, it succeeds. On further investigation it seems that requiring (without default features) just use_std succeeds, which is in fact the default.

If the crate does require that one always use use_std, then perhaps a compile time error would be helpful, like for example:

#[ cfg ( not ( feature = "use_std" ) ) ]
compile_error! ("`use_std` feature is currently required to build this crate");

[BurntSushi]

This is intentional, as documented in the changelog.

I don't think I knew about the existence of compile_error!. PRs are welcome. :-)

[cipriancraciun]

Pull request done: #482

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Regarding the changelog, indeed it is listed there exactly as it happens... However I guess not many read the changelogs of all their dependencies... (Indeed this is an "user" error, but to the "user" defense, there are so many dependencies these days...) :)