1 unstable release
0.1.0 | Oct 8, 2018 |
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#1004 in Embedded development
Used in mcf-config-demo-lib
2KB
A demo using const-fn as a configuration medium
The gist here:
- Embedded devices often need many tweaks to their libraries, to tune the behavior of a driver to a particular use case
- This is often seen with things like Buffer Sizes, where sometimes 512 bytes is enough, but other times 4K is needed
- Cargo's
cfg
feature flags are binary, and act as a union, so it is hard to provide compile-time settings, especially non-binary ones like size parameters, via feature flags min_const_fn
just stabilized, and will make it in time for1.31
This demo is a PoC of using const fn
to tweak compile time settings of a library, rather than relying solely on cfg
features.
The parts of this demo
mcf-config-demo-lib
- an example library, published on crates.iomcf-config-demo-settings
- a library crate, published on crates.io, containing default settingsmcf-config-demo-app
- a binary crate, that consumes the library above (not published on crates.io)mcf-config-demo-override
- a copy ofmcf-config-demo-settings
, but with some configuration items changed
To see how the demo works:
$ cd mcf-config-demo-app
$ cargo run
$ cargo run
Finished dev [unoptimized + debuginfo] target(s) in 0.00s
Running `target/debug/mcf-config-demo-app`
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Hello, world!
# uncomment the lines from Cargo.toml in the app folder
nano Cargo.toml
# ...
cargo run
cargo run
Finished dev [unoptimized + debuginfo] target(s) in 0.01s
Running `target/debug/mcf-config-demo-app`
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y halo thar!
License
Licensed under either of
-
Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
-
MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)
at your option.
Contribution
Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.