Implementing Type Ascription in Rust

Rust's type system is incredibly powerful, but sometimes the compiler can't infer the exact type you intend. Type ascription, also known as a "cast" in other languages, allows you to explicitly tell the compiler the type of a value. This challenge asks you to implement a function that performs type ascription, ensuring the compiler understands your intended type while respecting Rust's safety guarantees.

Problem Description

You need to implement a function ascribe_type that takes a value and a target type as input and returns a value of the target type. The function should handle basic numeric types (i32, i64, f32, f64) and return a Result to handle potential type conversion errors. The function should attempt to convert the input value to the target type. If the conversion is possible without loss of information (e.g., i32 to i64), it should perform the conversion. If the conversion would result in data loss (e.g., i64 to i32), it should return an Err result. If the types are fundamentally incompatible (e.g., i32 to f64), it should also return an Err result.

Key Requirements:

• Handle i32, i64, f32, and f64 types.
• Return a Result<T, String> where T is the target type.
• Return Ok(converted_value) if the conversion is successful.
• Return Err("Data loss during conversion") if the conversion would result in data loss.
• Return Err("Incompatible types for conversion") if the conversion is not possible.
• The function should be generic over the target type T.

Expected Behavior:

The function should correctly convert between compatible numeric types. It should also gracefully handle cases where conversion is not possible or would result in data loss, providing informative error messages.

Edge Cases to Consider:

• Conversion between signed and unsigned integers (e.g., i32 to u32). This challenge focuses on signed integers and floating-point numbers, so you can ignore unsigned integers.
• Conversion between floating-point types with different precisions (e.g., f32 to f64).
• Conversion between integer and floating-point types (e.g., i32 to f64).
• Invalid input types (e.g., trying to convert a string to an integer). This challenge focuses on numeric types, so you can assume the input is always one of the supported types.

Examples

Example 1:

Input: value: 10_i32, target_type: i64
Output: Ok(10)
Explanation: i32 to i64 is a safe conversion.

Example 2:

Input: value: 256_i64, target_type: i32
Output: Err("Data loss during conversion")
Explanation: i64 to i32 can result in data loss (256 > i32::MAX).

Example 3:

Input: value: 3.14_f32, target_type: f64
Output: Ok(3.140000104904175)
Explanation: f32 to f64 is a safe conversion.

Example 4:

Input: value: 10_i32, target_type: f64
Output: Ok(10.0)
Explanation: i32 to f64 is a safe conversion.

Constraints

• The function must be generic over the target type T.
• The input value must be one of i32, i64, f32, or f64.
• The target type T must be one of i32, i64, f32, or f64.
• The function should be reasonably efficient (avoid unnecessary allocations).

Notes

• Consider using Rust's TryInto trait for type conversions. However, be mindful of potential data loss.
• You'll need to use pattern matching to handle different input and target types.
• Think carefully about the conditions under which a conversion is considered safe and when it results in data loss.
• The ascribe_type function should be robust and handle various conversion scenarios gracefully.