Closure = Lambda(C++)

Closure is a function-like construct that can capture variables from the environment in which it is defined.
Rust (Closure) C++ (Lambda)
Can capture variables from their surrounding environment Yes Yes
Syntax |...| { ... } [ ] (parameters) { ... }
Different Types Move, Borrow Closure There are no types in lambda
Can place break in closure? No. You can do return. But rust does
not allow break due to ownership and borrow check rules 		Yes

Closure Types

Move Closure Borrow Closure
Definition A move closure captures variables from its environment by taking ownership of them (i.e., moving them)

fn main() {
    let x = 10;
    let closure = || {
        println!("Value of x: {}", x);
    };
    closure(); // This is a move closure since it captures 'x' by moving it.
    // 'x' cannot be used after this point, as it has been moved into the closure.
}
A borrow closure captures variables by borrowing them (i.e., creating references to them)

.iter() .map() .collect()

pipeline in Rust is a functional pattern that transforms a collection of input items into a new collection of a different type, element by element. 

3 stages:
.iter(): Takes JSON array & creates an iterator to look at each item (m) one by one
.map(|m| { ... }): runs once for every single element

Option Chaining:
  .get("name"): Try to find a field named "name".
  .or_else(|| m.get("model")): If "name" isn't there, fall back and try looking for "model" instead.
  .and_then(|x| x.as_str()): If a field was found, confirm it is actually a valid JSON string.
  .map(|s| s.to_string()): If it is a string, convert it from a borrowed &str slice into an owned String

.collect(): collects all the elements into a new collection (Vec, HashMap, etc.)