# Chapter

Chapter is a fork of the [`yharnam`](https://github.com/mystal/yharnam)
repository which is a rust parser and "runner" for [Yarn
Spinner](https://yarnspinner.dev/) v1 files.

This version started [as a fork](https://github.com/mystal/yharnam/pull/7), but
it seems like the original is no longer maintained. This version updates the
supported Yarn Spinner version to 2.3, and adds in additional methods and
functions that were not originally implemented.

Currently it is only capable of running pre-compiled Yarn Spinner files. A
parser for `.yarn` files is in progress.

> **NOTE** to run tests you will need to download a copy of
> [`ysc`](https://github.com/YarnSpinnerTool/YarnSpinner-Console), and use it to
> compile each of the test `.yarn` files.

Currently tested on Yarn Spinner
[2.3.0](https://github.com/YarnSpinnerTool/YarnSpinner/releases/tag/v2.3.0).

## Features

### random

> This feature is enabled by default

Use the `random` feature to enable random operations such as `dice`, `random`
and `random_range`. An additional non-standard function `random_test` is
provided. This takes a threshold between 0-1 and randomly generates a boolean
based on whether a random number is above or below the threshold (see `gen_bool`
from the `rand` crate).

In addition the random generator can be supplied a seed by calling
`vm.seed_random_generator(u64)`. See the random tests for an example.