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5 min readIn Rust, when you have a mutable vector attached to a struct instance, you can manipulate the vector using its reference. You can access the vector using the struct instance and then perform operations like adding elements, removing elements, or updating elements within the vector.To work with a mutable vector attached to a struct instance, you will need to use the &mut keyword to create a mutable reference to the struct instance.
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6 min readIn Rust macros, parsing an <output=t> parameter involves using the macro_rules! macro to define a macro that takes in an input token stream and matches it against the desired pattern. The <output=t> syntax indicates that the macro expects an input of type t and will produce an output based on that type.To parse <output=t> in a Rust macro, you can pattern match against the input token stream using match, if let, or other pattern matching techniques provided by the Rust language.
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4 min readIn Rust, variables are immutable by default, which means they cannot be reassigned once they have been defined. However, if you want to use the same variable multiple times with different values, you can simply shadow the variable by redefining it.For example, if you have a variable named "num" with the value 10, and you want to use it with a different value later in your code, you can simply redefine the variable like this: fn main() { let num = 10; // original value println.
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6 min readIn Rust, you can't add new fields to a struct with a method. Once a struct is defined, its fields are fixed and cannot be altered. If you need to add new data to a struct, you'll have to define a new struct with the additional field and use it instead. Alternatively, you can use associated types or enums to define a more flexible data structure.
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7 min readTo export a function written in Rust to C code, you need to use the #[no_mangle] attribute in Rust. This attribute prevents the Rust compiler from "mangling" the function name, which means that the function name will be preserved as-is when compiled to C code. You also need to use the extern "C" block to specify that the function should be compiled as C code.
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4 min readTo send a vector to a spawned thread in Rust, you can utilize the Arc and Mutex types from the standard library. By wrapping the vector in an Arc, which stands for atomic reference counter, and a Mutex, you can safely share the vector between threads. When you spawn a new thread, you can pass a clone of the Arc into the thread closure, allowing the thread to access and modify the shared vector. Remember to use lock() method of Mutex to access the inner data of the vector in a thread-safe manner.
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4 min readTo make a hash map with a struct in Rust, you first need to define the struct that you want to store in the hash map. You can then create a HashMap instance by specifying the struct type as the key and value types.
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4 min readTo pass a struct method as a callback in Rust, you can use a combination of closures and trait objects.First, define a trait that represents the callback behavior, with a method that will be called when the callback is invoked. Then, implement the trait for the struct that contains the method you want to use as the callback.Next, create a closure that calls the method on the struct when it is invoked. This closure can then be passed as the callback function.
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4 min readIn Rust, it is not possible to directly modify variables outside of a nested scope without using mutable references. This is because Rust has strict rules around ownership and borrowing to prevent data races and ensure memory safety.If you want to modify a variable outside of a nested scope, you can use mutable references to the variable.
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4 min readTo remove everything from a substring in Rust, you can use the replace method from the String type. You can replace the substring with an empty string, effectively removing it from the original string. Alternatively, you can use the replace_range method to replace a range of characters with an empty string. Both methods will modify the original string in place.[rating:c1abfe4e-5b23-47e2-a608-65097a225475]How to scrub a string of unwanted characters in Rust.
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7 min readIn Rust, you can overwrite multiple lines of text by using the BufWriter module from the standard library. This module allows you to efficiently write data to a buffer and then overwrite it in a file.To overwrite multiple lines in Rust, you can first create a File object using the OpenOptions module. You can then wrap the File object in a BufWriter object to write data to the file.Using the write_all method from the Write trait, you can write the new lines of text to the buffer.