The type of each element of a tuple can be different, so you can’t iterate over them. Tuples are not even guaranteed to store their data in the same order as the type definition, so they wouldn’t be good candidates for efficient iteration, even if you were to implement Iterator for them yourself. However, an … Read more
You can either: Add an allow attribute on a struct, module, function, etc.: #[allow(dead_code)] struct SemanticDirection; Add an allow as a crate-level attribute; notice the !: #![allow(dead_code)] Pass it to rustc: rustc -A dead_code main.rs Pass it using cargo via the RUSTFLAGS environment variable: RUSTFLAGS=”$RUSTFLAGS -A dead_code” cargo build
Since Rust 1.34, you can use extern crate self as my_crate, and use my_crate::Foo instead of $crate::Foo. https://github.com/rust-lang/rust/issues/54647 https://github.com/rust-lang/rust/pull/57407 (Credit: Neptunepink ##rust irc.freenode.net)
If you look at the String documentation, there are a few methods you could use. There’s String::from_utf8 that takes a Vec<u8>, and there’s also String::from_utf8_lossy which takes a &[u8]. Note that a Vec<T> is more-or-less an owned, resizable wrapper around a [T]. That is, if you have a Vec<u8>, you can turn it into a … Read more
The type &(&str, &str) comes from what iter() on a Vec returns: fn iter(&self) -> Iter<T> where Iter<T> implements Iterator<Item=&T>: impl<‘a, T> Iterator for Iter<‘a, T> { type Item = &’a T … } In other words, iter() on a vector returns an iterator yielding references into the vector. cloned() solves the problem because it … Read more
With the API you can use Builder::clang_arg with arbitrary arguments: let b = bindgen::builder().header(“foo.h”).clang_arg(“-I/path”); From the command line you can do the same by appending arguments after –, like: bindgen foo.h — -I/path
Are there any possible API like field_count() or is it only possible to get that via macros? There is no such built-in API that would allow you to get this information at runtime. Rust does not have runtime reflection (see this question for more information). But it is indeed possible via proc-macros! Note: proc-macros are … Read more
What do you want to happen if function() returns an Err result? You can’t use try!/? because it causes the containing function to return the same Err, but main() can’t return an Err (it returns (), not Result<…>). If you want to panic, you can use unwrap: function().unwrap(); If you want to ignore errors, discard … Read more
I don’t see how your request is possible, at least not without some exceedingly clever lock-free data structures; what should happen if multiple threads need to insert new values that hash to the same location? In previous work, I’ve used a RwLock<HashMap<K, Mutex<V>>>. When inserting a value into the hash, you get an exclusive lock … Read more
Just in case someone is looking for setting environment variable from source code, here is how you do it: use std::env; fn main() { // this method needs to be inside main() method env::set_var(“RUST_BACKTRACE”, “1”); } The benefit of this approach — in contrast to manually setting the env variable from PowerShell– is that you … Read more