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-An example of parsing a custom syntax within a `functionlike!(...)` procedural
-macro. Demonstrates how to trigger custom warnings and error messages on
-individual tokens of the input.
-
-- [`lazy-static/src/lib.rs`](lazy-static/src/lib.rs)
-- [`example/src/main.rs`](example/src/main.rs)
-
-The library implements a `lazy_static!` macro similar to the one from the real
-[`lazy_static`](https://docs.rs/lazy_static/1.0.0/lazy_static/) crate on
-crates.io.
-
-```rust
-lazy_static! {
- static ref USERNAME: Regex = Regex::new("^[a-z0-9_-]{3,16}$").unwrap();
-}
-```
-
-Compile and run the example by doing `cargo run` in the directory of the
-`example` crate.
-
-The implementation shows how to trigger custom warnings and error messages on
-the macro input. For example if you try adding an uncreatively named `FOO` lazy
-static, the macro will scold you with the following warning.
-
-```
-warning: come on, pick a more creative name
- --> src/main.rs:10:16
- |
-10 | static ref FOO: String = "lazy_static".to_owned();
- | ^^^
-```
-
-And if you try to lazily initialize `() = ()`, the macro will outright refuse to
-compile it for you.
-
-```
-error: I can't think of a legitimate use for lazily initializing the value `()`
- --> src/main.rs:10:27
- |
-10 | static ref UNIT: () = ();
- | ^^
-```