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update log-env-variable.md

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Ben 2024-04-29 17:46:42 +02:00
parent 1cac32ec4a
commit af344c0584
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12
src/development_tools/debugging/config_log/log-env-variable.md
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@ -4,20 +4,15 @@
[`Builder`] configures logging.
[`Builder::parse`] parses `MY_APP_LOG`
[`Builder::from_env`] parses `MY_APP_LOG`
environment variable contents in the form of [`RUST_LOG`] syntax.
Then, [`Builder::init`] initializes the logger.
All these steps are normally done internally by [`env_logger::init`].
```rust,edition2018
use std::env;
use env_logger::Builder;
fn main() {
Builder::new()
.parse(&env::var("MY_APP_LOG").unwrap_or_default())
.init();
Builder::from_env("MY_APP_LOG").init();
log::info!("informational message");
log::warn!("warning message");
@ -25,8 +20,7 @@ fn main() {
}
```
[`env_logger::init`]: https://docs.rs/env_logger/*/env_logger/fn.init.html
[`Builder`]: https://docs.rs/env_logger/*/env_logger/struct.Builder.html
[`Builder::from_env`]: https://docs.rs/env_logger/*/env_logger/struct.Builder.html#method.from_env
[`Builder::init`]: https://docs.rs/env_logger/*/env_logger/struct.Builder.html#method.init
[`Builder::parse`]: https://docs.rs/env_logger/*/env_logger/struct.Builder.html#method.parse
[`RUST_LOG`]: https://docs.rs/env_logger/*/env_logger/#enabling-logging