# yamlscript-crystal

**Repository Path**: mirrors_yaml/yamlscript-crystal

## Basic Information

- **Project Name**: yamlscript-crystal
- **Description**: YAMLScript binding library for the Crystal language
- **Primary Language**: Unknown
- **License**: MIT
- **Default Branch**: main
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2025-04-15
- **Last Updated**: 2026-03-22

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

<!-- DO NOT EDIT — THIS FILE WAS GENERATED -->

YS / YAMLScript
===============

Add Logic to Your YAML Files


## Synopsis

Load `file.yaml` with YS:
```yaml
!YS-v0:

# Get data from external sources:
names-url =:
  "https://raw.githubusercontent.com/dominictarr/\
   random-name/master/first-names.json"

name-list =: &first-names json/load(curl(names-url))

# Data object with literal keys and generated values:
name:: rand-nth(*first-names)
aka:: name-list.rand-nth()
age:: &num 2 * 3 * 7
color:: &hue qw(red green blue yellow)
          .shuffle()
          .first()
title:: "$(*num) shades of $(*hue)."
```

and get:
```json
{
  "name": "Dolores",
  "aka": "Anita",
  "age": 42,
  "color": "green",
  "title": "42 shades of green."
}
```


## Description

[YS](https://yamlscript.org) is a functional programming language with a clean
YAML syntax.

YS can be used for enhancing ordinary [YAML](https://yaml.org) files with
functional operations, such as:

* Import (parts of) other YAML files to any node
* String interpolation including function calls
* Data transforms including ones defined by you

This YS library should be a drop-in replacement for your current YAML loader!

Most existing YAML files are already valid YS files.
This means that YS works as a normal YAML loader, but can also evaluate
functional expressions if asked to.

Under the hood, YS code compiles to the Clojure programming language.
This makes YS a complete functional programming language right out of the box.

Even though YS compiles to Clojure, and Clojure compiles to Java, there is no
dependency on Java or the JVM.
YS is compiled to a native shared library (`libyamlscript.so`) that can be used
by any programming language that can load shared libraries.

To see the Clojure code that YS compiles to, you can use the YS
CLI binary `ys` to run:

```text
$ ys --compile file.ys
(let
 [names-url "https://raw.githubusercontent.com/dominictarr/random-name/master/first-names.json"
  name-list (_& 'first-names (json/load (curl names-url)))]
 (%
  "name" (rand-nth (_** 'first-names))
  "aka" (rand-nth name-list)
  "age" (_& 'num (mul+ 2 3 7))
  "color" (_& 'hue (first (shuffle (qw red green blue yellow))))
  "title" (str (_** 'num) " shades of " (_** 'hue) ".")))
```

## Crystal Usage

Here's a simple example of using the YAMLScript Crystal binding:

```crystal
require "yamlscript"

# YAMLScript code
ys_code = <<-YS
!YS-v0
inc: 41
YS

# Load and evaluate the YAMLScript
result = YAMLScript.load(ys_code)
puts "Result: #{result}"  # Output: Result: 42

# Regular YAML also works
yaml_code = "foo: bar"
result = YAMLScript.load(yaml_code)
puts "YAML result: #{result["foo"]}"  # Output: YAML result: bar
```

## Development

To build and run tests:

```bash
# Clone the repository
git clone https://github.com/yaml/yamlscript.git
cd yamlscript/crystal

# Build the binding and copy required libraries
make build

# Run the tests
make test

# Run the example
make run-example
```

## See Also

* [YS Web Site](https://yamlscript.org)
* [YS Blog](https://yamlscript.org/blog)
* [YS Source Code](https://github.com/yaml/yamlscript)
* [YS Samples](https://github.com/yaml/yamlscript/tree/main/sample)
* [YS Programs](https://rosettacode.org/wiki/Category:YAMLScript)
* [YAML](https://yaml.org)
* [Clojure](https://clojure.org)


## Authors

* [Josephine Pfeiffer](https://github.com/pfeifferj)
* [Ingy döt Net](https://github.com/ingydotnet)

## License & Copyright

Copyright 2022-2025 Ingy döt Net <ingy@ingy.net>

This project is licensed under the terms of the `MIT` license.
See [LICENSE](https://github.com/yaml/yamlscript/blob/main/License) for
more details.