rustlings/exercises/closures

Closures

Closures are a common programming concept found in many languages, but are primarily associated with 'functional' programming styles. Closure are anonymous functions (i.e. unlike regular functions, they don't have a name) that may access some variables from their enclosing scope (they 'close' over their scope, capturing variables).

Closures are often used as arguments to higher order functions (functions which take other functions as parameters), e.g. map(), filter(), reduce() et al on iterators, but aren't restricted to these cases.

Rust's ownership model means that we may need to think about how captured values are treated: copied, moved, or borrowed immutably or mutably.

Further information

• Closures: Anonymous Functions that Can Capture Their Environment