my_log { { $($arg:tt)+ } => { eprintln!("{}:{}: {}", file!(), line!(), format_args!($($arg)+)); } } } #![allow(unused)] fn main() { let x = 10u8; // Format specifiers: // - `x` says print as hex // - `#` says prefix with '0x' // - `04` says...
foo { ($e:expr) => {println!("foo expr: {}", $e); }; }macro_rules!bar{ ($l:literal) => {println!("bar literal: {}", $l); }; ($e:expr) => {println!("bar expr: {}", $e); }; }macro_rules!baz { ($e:expr) => {println!("baz expr: {}", $e); }; ($l...
macro_rules!vec_strs{($($element:expr)// 重复的内容是元变量,类型为表达式,// 分隔符*// 匹配0个或者多个)=>{{letmutv=Vec::new();$(v.push(format!("{}",$element));)*// 重复性的将匹配到的$element以字符串的形式存入到vec中v// 最终展开产物}};}fnmain(){lets=vec_strs![1,"a",...
baz{($e:expr)=>{println!("baz expr: {}",$e);};($l:literal)=>{println!("baz literal: {}",$l);}}fnmain(){foo!(1);foo!(1+2);bar!(1);bar!(1+2);baz!(1);baz!(1+2);}// Output:// foo expr: 1// foo expr: 3// bar literal: 1// bar expr: 3// baz expr: ...
format: String, warn_threshold: Option<f32>, bad_threshold: Option<f32>, } #[async_trait] impl Component for LoadAvg { async fn print(self: Box<Self>, _global_config: &GlobalConfig, _width: Option<usize>) { self.print_or_error() .unwrap_or_else(|err| println!("LoadAvg error: ...
// | formatSpecifier| Emitted for format specifiers `{:?}` in `format!`-like macros.| // // - For operators: // + // [horizontal] // operator:: Emitted for general operators. // arithmetic:: Emitted for the arithmetic operators `+`, `-`, `*`, `/`, `+=`, `-=`, `*=`...
/// ```no_run /// loop { /// println!("Hello, world"); /// } /// ``` compile_fail 告诉rustdoc 应该编译失败。如果便已通过,测试失败。但是需要注意现在版本 Rust 编译失败可能在将来 Rust 版本编译成功。/// ```compile_fail /// let x = 5; /// x += 2; // shouldn't compile...
println!("S: {}", s);2 changes: 1 addition & 1 deletion 2 crates/jsdoc/src/input.rs Original file line numberDiff line numberDiff line change @@ -54,7 +54,7 @@ impl_slice!(Range); impl_slice!(RangeFrom); impl_slice!(RangeTo); impl<'i> From<Input<'i>> for Text { impl...
Format String Completion Source:format_like.rs "Result {result} is {2 + 2}"is expanded to the"Result {} is {}", result, 2 + 2. The following postfix snippets are available: format→format!(…) panic→panic!(…) println→println!(…) ...
println!("{}", formatted_pi);// prints 3.14 } Thepivariable holds a floating point value; with the format specifier:.2, you can instruct theformat!macro to displaypiwith two decimal places. Theformat!macro is one of the many methods of string formatting with Rust. Depending on your requ...