Generics

Question 1

What is Monomorphization

Answer 1

The process of turning generic code into specific code by filling in the concrete types that are used when compiled

Question 2

A Good Example of Monomorphization use case

Answer 2

on Monomorphizing Hashmap Rust is able to create a seperate hashing function for each type so its more optimized.

Question 3

Downside of Monomorphization

Answer 3

1. The downsides is that your binary ends up being larger because u need to generate a copy of the type or the function for every type that is used with.
2. the code can be little less efficient because if u have 2 different functions making the computer have to jump to different seperate regions of memory
3. could be expensive if u generate ridiciolus amount of types

Question 4

What is a Static Dispatch

Answer 4

Static dispatch is when the concrete implementation of a method is determined at compile time

Question 5

Advantages of Static Dispatch

Answer 5

Maximum performance

No runtime overhead

Enables inline optimizations

Type checking at compile time

Question 6

Disadvantages of Static Dispatch

Answer 6

Increases binary size (code bloat)

Can’t handle cases where types are only known at runtime

All possible types must be available at compile time

Question 7

When to use Static Dispatch

Answer 7

1. Perfomance is critical
2. Types are known at compile time
3. Working with generic code

Question 8

When to use Dynamic Dispatch

Answer 8

1. Runtime Flexibility
2. Hetergonus Collections meaning that the collection has different types
3. if u want to use external Code

Question 9

Why do u need to know size at compile time

Answer 9

it needs to know how much to allocate stack memory for the variables, to generate efficient the compiler must know the size

how to layout the structs in the memory

Track ownership and lifetime

Question 10

example of things that doens’t have any size on compile time if u make as argument for a functions

Answer 10

str,
[u8]

Question 11

what is a Vtable

Answer 11

virtual table is a little data structure that has a pointer to each methods for the trait for the type

Question 12

What is a Fat pointer

Answer 12

a pointer that contains more than 1 pointer

Question 13

Generic Types Vs Associated Types

Answer 13

Generic Types vs Associated Types:

Generic types (like trait Drive<T>) allow multiple implementations of the same trait for a single type, each with different type parameters.</T>

Associated types (like trait Drive { type DriveType; }) restrict you to only one implementation per type, as you can only specify one associated type per implementation.