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6 min readIn Rust, primitive types are considered "sync" because they are implemented with thread-safe logic. This means that these types can be safely shared between multiple threads without causing any data races or synchronization issues. The "sync" property ensures that operations on these types are atomic and can be performed concurrently without compromising the integrity of the data.
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7 min readTo convert a u32 datatype to a bigint in Rust, you can use the From trait to perform the conversion. You can simply use the from method provided by the num-bigint crate to convert a u32 value to a BigInt type. Here is an example code snippet: use num_bigint::BigInt; fn main() { let u32_value: u32 = 12345; let bigint_value: BigInt = BigInt::from(u32_value); println!("Converted BigInt value: {}", bigint_value); } In this code snippet, we first define a u32 value.
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5 min readIn Rust, you can set a variable to an implementation of a generic typed trait by using a trait object. To do this, you need to create a trait that defines the behavior you want your types to have. Then, you can implement this trait for your specific types.To set a variable to an implementation of a generic typed trait, you can use a trait object, which allows you to store any type that implements the trait.
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4 min readTo write a formatted string up to a buffer size in Rust, you can use the write method from the std::fmt::Write trait. This method allows you to write a formatted string to a provided buffer, up to a specified size. You can create a buffer using the write! macro, which takes the buffer as the first argument, followed by the format string and any additional arguments to be formatted.
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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.