Error while using Orbtk gui in rust

error[E0554]: #![feature] may not be used on the stable release channel
–> /home/ebin/.cargo/registry/src/github.com-1ecc6299db9ec823/orbtk-0.2.29/src/lib.rs:4:1
|
4 | #![feature(const_fn)]
| ^^^^^^^^^^^^^^^^^^^^^

error: aborting due to previous error

For more information about this error, try rustc --explain E0554.
error: Could not compile orbtk.

To learn more, run the command again with --verbose.

what is the reason for this error…

Looks like this crate can be used only with nightly compiler, but a quick search through the docs didn’t reveal anything about it. Could someone provide a more full explanation?

As for the fix, just install the nightly toolchain (rustup toolchains add nightly) and use it for the project (cargo +nightly build).

Also make sure you have the latest compiler version. Older versions (such as the ones frozen in time in Linux distros) may be older than this feature.