ref

A ref cell library for gleam. The implementation uses actors on the erlang target for keeping track of the values of references, so a new process is spawned for each mutable reference you create. These mutable references should only be used if mutability is absolutely required. Immutability should always be preferred, and this implementation loses the performance benefits that mutability generally provides.

Types

RefCell

opaque </>

The reference cell type for holding mutable data

pub opaque type RefCell(a)

Functions

cell

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pub fn cell(contents: a) -> RefCell(a)

Public constructor for creating a new RefCell. The initial value is passed, and a RefCell containing that value is returned.

get

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pub fn get(cell: RefCell(a)) -> a

Used for extracting the held data in a RefCell. Once the value has been extracted with this function, any mutations on the Cell will not affect the data already extracted.

main

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pub fn main() -> Int

map

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pub fn map(subj: RefCell(a), f: fn(a) -> b) -> RefCell(b)

Map the result of a function taking a Cell’s contents into a new RefCell. No mutation takes place

set

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pub fn set(cell: RefCell(a), operation: fn(a) -> a) -> a

Pass a function that takes and returns the inner type of the RefCell, and set the contents of the cell to its return value