Like an array, but rounder.
Hoopy is a circular array data type. It extends Array
so that out-of-bounds indices wrap back round to the start of the array (or if they're negative indices, they wrap back round to the end of the array).
If you want a fixed-length buffer for streamed I/O, Hoopy can do that for you.
Via npm
:
npm i hoopy --save
Or if you just want the git repo:
git clone git@gitlab.com:philbooth/hoopy.git
const Hoopy = require('hoopy');
const hoopy = new Hoopy(10); assert(Array.isArray(hoopy));
You must pass a size
argument to the Hoopy
constructor, otherwise it will throw.
for (let i = 0; i < hoopy.length; ++i) { hoopy[i] = i; console.log(hoopy[i]); }
You can read and write array items using square brackets for indexing as you would with a normal array. However, if you write to an out-of-bounds index, it will not increase the length of the array. Instead the index is applied modulo the array length, wrapping back round to the start. Negative indices work in reverse, wrapping back round to the end of the array.
The methods push
, pop
, shift
and unshift
will throw if called. Future versions of the library may implement sane behaviour for them. All of the other Array
methods work normally.
hoopy.grow(50);
The grow
method adds items to the array. It takes one argument, which is the number of items to grow the array by. The new length of the array will be the old length plus the number you pass to grow
.
If the current state of the array includes overflowed indices, grow
will take care to move those items in to the freshly-created available space, so that the correct order is maintained for your data.
The caller is responsible for ensuring they don't overwrite unprocessed items. If you need to increase the size of the array, you must call grow
.
Yes.
To install the dependencies:
npm i
To run the tests:
npm t
To lint the code:
npm run lint
MIT.