第三届中国 Rust 开发者大会 PromQL Got a BOOST: 用 Rust 重写 Prometheus 的查询引擎 Ruihang Xia @greptime.com Ruihang GitHub: waynexia Losing hair at Greptime Wanna sleep 10 hrs/day Learn JS every year Healing

`foo` and write its address at 0x2000” … 0x00000000 … Address-list section: “IAT” in Windows, “GOT” in Linux Cross-binary calls are typically indirect – carry a virtual-call overheadWindows 8binary they got right.” Fangrui Song, LLD maintainer https://maskray.me/blog/2021-06-13-dependency-related-linker-options 21Position Independent Code: GOT code call rip–12 code call [ ] .got 0x123 0x123 0x789 .got+42 .got+42 code call 0x789 22 0x789Position Independent Code: GOT • For all (default visibility) calls from a shared-lib! • This code - void f() { ... } void g() { f(); } Will

it. From your shell, run the uninstall script: $ rustup self uninstall Troubleshooting If you’ve got Rust installed, you can open up a shell, and type this: $ rustc --version You should see the version note: expected type `bool` found type `{integer}` The error indicates that Rust expected a bool but got an integer. Rust will not automatically try to convert non-boolean types to a boolean, unlike languages references into the String remain valid. Remember the bug in the program in Listing 4-11, when we got the index to the end of the first word but then cleared the string so our index was invalid? That code

unwrap(); }); let received:String = rx.recv().unwrap(); // 阻塞等待，直到接收到一个消息 println!("Got: {}", received); } 例如上述代码编译通过，但是在运行过程中会死锁。而 rust 的编译器无法识别 此类错误。Rust 对安全的理解是死锁不属于内存安全问题。 Rust 在并发上的改进是： println!("val is {}", val); }); let received = rx.recv().unwrap(); println!("Got: {}", received); } 这里尝试在通过 tx.send 发送 val 到通道中之后将其打印出来。允许这 么做是一个坏主意：一旦将值发送到另一个线程后，那个线程可能会在我们再 次 thread::sleep(Duration::from_secs(1)); } }); for received in rx { println!("Got: {}", received); } } 这一次，在新建线程中有一个字符串 vector 希望发送到主线程。我们遍历他 们，单独的发送每一个字符串并通过一个 Duration 值调用

^ :5:27: note: expected a constant of type 'long unsigned int', got 'double' https://godbolt.org/z/9Wh9Pr4cP77 David Olsen – Generic Programming CppCon 2024 Class Template ^ :5:27: note: expected a constant of type 'long unsigned int', got 'double' https://godbolt.org/z/9Wh9Pr4cP78 David Olsen – Generic Programming CppCon 2024 Class Template 6 | std::array<1, 2> c; | ^ :6:20: note: expected a type, got '1' https://godbolt.org/z/9Wh9Pr4cP79 David Olsen – Generic Programming CppCon 2024 Class Template

SIGTSTP ctrl-b back one char ctrl-f forward one char ctrl-left go to left word boundary ctrl-right got to right word boundar ctrl-a go to start ctrl-e go to end ctrl-h delete char to left of cursor one line is entered. // The question method doesn't emit this event. console.log('line event: got ' + line); }); intf.question('What is your name? ', function (name) { console.log('Hello, ' intf.close(); process.stdin.destroy(); // allows program to terminate } else { console.log('got ' + line); intf.prompt(); } }); // Asynchronous version function completer(partial, cb) {

is, of course, assuming that you installed under C:\PP or /usr/lib/fpc/NNN, respectively. If you got no error messages, the compiler has generated an executable called hello.exe under DOS, OS/2 or WINDOWS beginning of a file, so it interprets it as a UTF-8 file. Error: Compile time expression: Wanted arg1 but got arg2 at arg3 The type-check of a compile time expression failed. Note: APPTYPE is not supported by is a method for an object as exported. Error: Call by var for arg no. arg1 has to match exactly: Got "arg2" expected "arg3" When calling a function declared with var parameters, the variables in the

12 print("Error: too few arguments. Got " + str(len(sys.argv) -1) + " , Expected 10") 13 elif (len(sys.argv) > 11): 35 14 print("Error: too many arguments. Got , " + str(len(sys.argv) -1) + ", Expected 5): 13 print("Error: too few arguments. Got " + str(len(sys.argv) -1) + " , Expected 4") 14 elif (len(sys.argv) > 5): 15 print("Error: too many arguments. Got , " + str(len(sys.argv) -1) + ", Expected 5): 9 print("Error: too few arguments. Got " + str(len(sys.argv) -1) + " , Expected 4") 10 elif (len(sys.argv) > 5): 11 print("Error: too many arguments. Got , " + str(len(sys.argv) -1) + ", Expected

{ if value < 1 || value > 100 { panic!("Guess value must be between 1 and 100, got {}.", value); } Guess { value } } pub fn value(&self) -> i32 { self { if value < 1 || value > 100 { panic!("Guess value must be between 1 and 100, got {}.", value); } Guess { value } } } #[cfg(test)] mod tests { use super::*; i32) -> Guess { if value < 1 { panic!("Guess value must be between 1 and 100, got {}.", value); } Guess { value } } } # # #[cfg(test)] # mod tests { # use super::*;

Deducing this this)) See also See also C++Weekly Episode 318: My Meetup Got Nerd Sniped! C++Weekly Episode 318: My Meetup Got Nerd Sniped! Tip: attend your local meetup! If you don't have one, Tip: attend quotes. I didn't make this technique up for the talk - guess where I got it? I didn't make this technique up for the talk - guess where I got it? // a string parser return quote_parser < str_parser > quote_parser; this: if you've got an Applicative functor, that's good; The moral is this: if you've got an Applicative functor, that's good; if you've also got a Monad, that's even better! if you've also got a Monad, that's