diff options
Diffstat (limited to 'samples/rust/rust_print_main.rs')
-rw-r--r-- | samples/rust/rust_print_main.rs | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/samples/rust/rust_print_main.rs b/samples/rust/rust_print_main.rs index 7935b4772ec6..7e8af5f176a3 100644 --- a/samples/rust/rust_print_main.rs +++ b/samples/rust/rust_print_main.rs @@ -34,6 +34,24 @@ fn arc_print() -> Result { // Uses `dbg` to print, will move `c` (for temporary debugging purposes). dbg!(c); + { + // `Arc` can be used to delegate dynamic dispatch and the following is an example. + // Both `i32` and `&str` implement `Display`. This enables us to express a unified + // behaviour, contract or protocol on both `i32` and `&str` into a single `Arc` of + // type `Arc<dyn Display>`. + + use core::fmt::Display; + fn arc_dyn_print(arc: &Arc<dyn Display>) { + pr_info!("Arc<dyn Display> says {arc}"); + } + + let a_i32_display: Arc<dyn Display> = Arc::new(42i32, GFP_KERNEL)?; + let a_str_display: Arc<dyn Display> = a.clone(); + + arc_dyn_print(&a_i32_display); + arc_dyn_print(&a_str_display); + } + // Pretty-prints the debug formatting with lower-case hexadecimal integers. pr_info!("{:#x?}", a); |