YS — YAML Done Wisely

YS Summer Break

Ingy döt Net — Fri, 01 Aug 2025 00:00:00 +0000

When I started the Summer of YS blog series on June 1st, I committed to writing a blog post every day until September 1st (92 days in a row).

Today it's Friday, August 1st, 2025 and today's post is number 62.

It's also the last one!

The loop and more loops

Ingy döt Net — Thu, 31 Jul 2025 00:00:00 +0000

The looping function that offers the most control in YS is called loop. It's also the most verbose.

There are lots of alternatives that are more specific and require less code, but they don't let you do everything, like decide when to stop.

We'll talk about both today.

Sometimes it's hard to be lazy

Ingy döt Net — Wed, 30 Jul 2025 00:00:00 +0000

YS (being Clojure) is a functional language with immutable data structures and lazy evaluation.

Laziness is cool because you can do complicated operations on large (even infinite) sequences without having to load everything into memory.

But laziness can be very confusing when you're not used to it or you don't expect it.

Is JSON really a subset of YAML?

Ingy döt Net — Tue, 29 Jul 2025 00:00:00 +0000

YAML is a superset of JSON.

This is a basic truth about YAML.

I assume that in 2025, most people who use YAML and JSON regularly already know this.

Today I'll say a bit more about this and how it came to be.

YS on jank, bb and ys

Ingy döt Net — Mon, 28 Jul 2025 00:00:00 +0000

Last Friday we got a YS program running on Go using Glojure.

Today we'll show how to run it on 3 other Clojure platforms:

jank - Clojure hosted by C++ on LLVM
bb - Clojure using SCI and GraalVM
ys - YS can run Clojure from a YS ys -c compile command

Fun in the SundaYS

Ingy döt Net — Sun, 27 Jul 2025 00:00:00 +0000

Let's do a Fun FridaYS post on Sunday.

I wrote the YS one liner to open 40 random Rosetta Code tasks written in Clojure.

bash $ cd RosettaCodeData $ vim $(ys -e 'sh-out("find Lang/Clojure"):lines:shuffle .mapv(fn([d] sh-out("ls $d"):lines .mapv(fn([f] say("$d/$f")))))' | grep -v '\-[0-9]' | head -40)

Pretty cool, right?

The YS Core YAML-Schema

Ingy döt Net — Sat, 26 Jul 2025 00:00:00 +0000

The term "YAML Schema" is a bit of unfortunate history.

It's not the YAML version of a JSON Schema.

In my opinion it needs to be renamed because it's not a schema in the typical sense of the word. The term has been part of the YAML spec since the beginning.

Let's use the term "YAML-Schema" instead of "YAML Schema" to be clear that this is not a typical schema applied to a YAML file.

Typically a schema is a set of rules that are used to validate data.

A YAML-Schema is a set of rules about how untagged nodes are implicitly tagged during the loading process.

Allow me to explain.

YS on the Go

Ingy döt Net — Fri, 25 Jul 2025 00:00:00 +0000

Yesterday I hinted at the idea of YS hosted on Go.

This doesn't mean that YS would be rewritten in Go or that it wouldn't compile to Clojure. The Lisp is still essential to YS.

Where I was going was the possibility of creating a Clojure hosted on Go, which I've been thinking about for a while.

Go is the backbone of technologies like Kubernetes, where YS wants to provide a more powerful YAML experience.

As I was getting ready for bed, the word "Glojure" popped into my head.

What a perfect name for a Go hosted Clojure!

Why YS Chose Clojure

Ingy döt Net — Thu, 24 Jul 2025 00:00:00 +0000

So YS compiles to Clojure.

It also has a Clojure runtime and access to the Clojure ecosystem.

It's also written in Clojure. (It didn't have to be. The compiler could have been written in any language.)

Why Clojure?

I'll explore that topic today.

YS Streaming Mode

Ingy döt Net — Wed, 23 Jul 2025 00:00:00 +0000

We've seen before that YS can work with YAML files that contain multiple documents. "Document" is the YAML term for a single top level node (object).

YS returns the last document in the file by default.

YS can also load all the documents in the file.

This is called streaming mode, and we'll learn more about it today.

ys and yq

Ingy döt Net — Tue, 22 Jul 2025 00:00:00 +0000

Today I met Mike Farah, the creator of yq!

I help maintain the go-yaml YAML framework for Go, and am working with Mike to help it fix certain issues in yq.

It looks like a promising future for both go-yaml and yq.

It turns out that YS has a lot of crossovers with yq.

Let's take a closer look at how they compare.

Calling Shell Commands from YAML

Ingy döt Net — Mon, 21 Jul 2025 00:00:00 +0000

Wouldn't it be handy to get data from shell commands in YAML?

Well you can, and it's really easy.

YS has a bunch of functions in its Standard Library for calling shell commands, and passing data to and from them.

Let's take a look...

YAML Best Practices

Ingy döt Net — Sun, 20 Jul 2025 00:00:00 +0000

YAML has a Core Development Team of five people that I am a member of.

In May 2024, 4 of us met in Berlin. One of the things we did was to write a list of best practices for YAML. We came up with a list of 40 or so things that we all agreed on.

Today I'll share some of those with you.

YAML Explicit Keys and YS

Ingy döt Net — Sat, 19 Jul 2025 00:00:00 +0000

Did you know that in YAML you can write:

yaml ? foo : bar

instead of:

yaml foo: bar

The ? is called an explicit key indicator.

But why would you want to use it?

It's not often useful in YAML config files, but it is actually useful in YS code.

Fun FridaYS — Dragon Curve

Ingy döt Net — Fri, 18 Jul 2025 00:00:00 +0000

On Friday June 27th we found a task on Rosetta Code and converted the Clojure solution to YS.

Let's do that again today.

YS Comment Syntax

Ingy döt Net — Thu, 17 Jul 2025 00:00:00 +0000

What is the syntax for comments in YS?

Well that's simple.

YS code is YAML, so the comment syntax is the same as YAML.

Well, there's a little bit more to it than that.

Making YS be Valid YAML

Ingy döt Net — Wed, 16 Jul 2025 00:00:00 +0000

I'll say it again. All YS syntax is 100% YAML. The YS compiler uses a third party YAML parser so there is no way that YS code cannot be YAML.

YS code also uses a lot of Clojure syntax. This makes sense since the code gets compiled to Clojure in the end.

Some Clojure code looks a lot like YAML but with subtle differences.

Today we'll talk about the little gotchas that can trip you up when you're writing YS code, and how to work around them.

YS Currying in YAML Configs

Ingy döt Net — Tue, 15 Jul 2025 00:00:00 +0000

In functional programming, currying is a technique where a function that takes multiple arguments is called with fewer arguments than it takes and returns a function that takes the remaining arguments.

In Clojure and YS, the partial function is used to create a curried function.

Here's an example:

bash $ ys -e ' multiply-by-6 =: partial(mul 6) multiply-by-7 =: mul.partial(7) say: multiply-by-6(7) say: multiply-by-7(6) ' 42 42

That's neat but how is it useful in YAML configs?

YS Mapping Key Uniqueness

Ingy döt Net — Mon, 14 Jul 2025 00:00:00 +0000

I've said it before, but YS code is 100% valid YAML.

Here's a YS program:

!ys-0 say: 'You say Goodbye' say: 'I say Hello'

YAML says that mapping keys must be unique.

That program seems to be a YAML mapping with two keys that are the same.

How can this be valid YAML?

YS Testing Part 2

Ingy döt Net — Sun, 13 Jul 2025 00:00:00 +0000

Yesterday we talked about writing tests in YS.

We also introduced the ys::taptest library, but we didn't really cover how it works.

Let's take a closer look...

YS Testing

Ingy döt Net — Sat, 12 Jul 2025 00:00:00 +0000

YS is a great language for writing tests in.

Why?

Well tests are mostly data. Inputs and outputs for some code you want to test. Code is usually in functions, and functions usually have names and names are just strings and strings are just data.

YAML is a great format for data. YS is YAML with code (expressed as YAML data).

So it seems like YS should be a great language for writing tests in. And it is.

YAML gets YS in PHP, C#, Lua & Haskell

Ingy döt Net — Fri, 11 Jul 2025 00:00:00 +0000

YS is a YAML loader module. On one hand it does have super powers, but on the other hand it's just a plain YAML loader.

A YAML loader is a utility that can turn YAML into a data structure. Every modern language has a YAML loader. Most have many.

YS is the first YAML loader that was made for every programming language.

Well that's the goal anyway.

For the past year it's only had loaders for 11 languages: Clojure, Crystal, Go, Java, Julia, NodeJS, Perl, Python, Raku, Ruby, and Rust.

Until this week, that is...

Building YS

Ingy döt Net — Thu, 10 Jul 2025 00:00:00 +0000

Try running these commands on Linux or Mac:

bash git clone https://github.com/yaml/yamlscript cd yamlscript make install

Chances are that everything will just work. You'll have new builds of ~/.local/ys and ~/.local/lib/libys.so (.dylib on a Mac).

YS actually has a lot of heavy dependencies like Clojure, Java, Maven, GraalVM, etc.

So how does it just work?

Today I'll tell you!

Fun with Function Tags

Ingy döt Net — Wed, 09 Jul 2025 00:00:00 +0000

We've seen different ways to call YS functions in YAML.

Say we have this file.yaml:

yaml people: - Alice - Bob - Charlie

What if we wanted to reverse the list?

About the -0

Ingy döt Net — Tue, 08 Jul 2025 00:00:00 +0000

The current version of YS as of today is 0.2.1.

I'm sure you've noticed the -0 part of the !ys-0 tag by now.

YS intends to be a "versioned programming language", where v2 can behave very differently from v1 while still being able to use v1 libraries and such.

Today I'll tell you a bit more about the versioning and how things are expected to work.

Remember, we are still officially at v0 so even the rules of how versioning works are not yet set in stone!

YS External Modules

Ingy döt Net — Mon, 07 Jul 2025 00:00:00 +0000

Reusing code is the cornerstone of good programming.

If you see duplicate logic, refactor it into a function.

If you see a function that's used in multiple places, move it to a module.

If you need the module in multiple repos, publish it online.

Today let's see how we'd go about refactoring a YS program's useful functions into an external module for reuse by anyone.

YS Regular Expressions

Ingy döt Net — Sun, 06 Jul 2025 00:00:00 +0000

All modern programming languages have regular expressions.

YS has them too.

Perl was the first modern language to include them as a built-in feature.

YS regexes borrow quite a bit from Perl's, but also behave as functions that return matching results (unlike Perl, and more like all the others).

Let's take a look...

The Special Little Symbol

Ingy döt Net — Sat, 05 Jul 2025 00:00:00 +0000

Yesterday I showed you a FizzBuzz solution in YS. Here it is again:

```yaml !ys-0

defn main(n=100): each x (1 .. n): !say or? _ x: str ((x % 3).! &&& 'Fizz'): ((x % 5).! &&& 'Buzz') ```

See that _ sitting there in the middle all by itself?

What's that all about?

Well _ is a special symbol in YS, and it means different things in different contexts.

Exercism Comparisons

Ingy döt Net — Fri, 04 Jul 2025 00:00:00 +0000

Last week I told you about YS on Rosetta Code and yesterday I told you about YS on Exercism.

Today I'm going to show you how to compare solutions to the same Rosetta Code task using all the Exercism languages!

YS Exercism

Ingy döt Net — Thu, 03 Jul 2025 00:00:00 +0000

Ever heard of a YS Exorcism?!

Sounds pretty scary!

A YS Exercism on the other hand is one of the best ways to learn YS.

Exercism.org is a free programming learning site with tracks for over 75 languages!

YS / Java Interoperability

Ingy döt Net — Wed, 02 Jul 2025 00:00:00 +0000

We know that YS is made from Clojure and the Clojure is made from Java. Clojure code is interoperable with Java code.

So is YS interoperable with Java?

Yes, YS is can call Java methods on its objects.

Let's see how to do it.

YS Symbols

Ingy döt Net — Tue, 01 Jul 2025 00:00:00 +0000

Today I'd like to show you why I love how YS handles symbols.

Symbols are used to represent variables, functions, and other names in the language.

All the shorties I showed you yesterday were symbols. Symbols that resolved to functions.

YS Shorties

Ingy döt Net — Mon, 30 Jun 2025 00:00:00 +0000

From the start, YAML has always been about making data clean and easy to read.

This carries over to YS code as well.

Even though YS code compiles to Clojure, YS often has shorter alternatives for Clojure's commonly used and longer function names.

The Truth about Sunday

Ingy döt Net — Sun, 29 Jun 2025 00:00:00 +0000

Or better yet...

The Sunday about Truth

If I were to tell you that YS has a system,
to determine if something is true...
I'd deserve hell and fire,
and be labeled a liar,
for in total truth, YS has 2!

Dot Chain Special Operators

Ingy döt Net — Sat, 28 Jun 2025 00:00:00 +0000

Yesterday we wrote a YS program by porting a Clojure program from Rosetta Code.

We introduced a bunch of new things without really explaining them.

Today I'll explain a set of them.

Fun FridaYS — Rosetta Code

Ingy döt Net — Fri, 27 Jun 2025 00:00:00 +0000

It's Friday and I feel like having some fun. With YS, of course.

Rosetta Code is a super fun site that has over 1000 programming tasks that people solve in nearly 1000 programming languages (including YS). If you've never heard of it, you should check it out.

Let's solve a task in YS that hasn't been solved yet!

YS Mode Switching

Ingy döt Net — Thu, 26 Jun 2025 00:00:00 +0000

I've mentioned YS "modes" in passing several times in this series.

YS has 3 modes: data, code, and bare.

Fully understanding modes is one of the most important things to understand about YS.

Today I want to go deeper on the details of modes. This will make everything else much easier to explain going forward.

AI + Clojure Functions in YAML

Ingy döt Net — Wed, 25 Jun 2025 00:00:00 +0000

Yesterday we learned that all YS YAML input compiles to Clojure (Lisp) before being evaluated by a native binary Clojure interpreter runtime.

Does this mean that you could write Lisp functions in your YAML data files? And then call them on your data?

Of course it does!

How Does YS Work?

Ingy döt Net — Tue, 24 Jun 2025 00:00:00 +0000

What if I told you that...

YS is made out of Java
YS uses no JVM
YS is a binary Executable
YS is also a Shared Library
YS is actually a Lisp
YS can use S-Expressions
YS prefers YeS-Expressions
YS can use modules written in:
- YS
- Any other language

Make sense?

YS One Liners

Ingy döt Net — Mon, 23 Jun 2025 00:00:00 +0000

There's almost nothing I like more about programming than one liners.

A one liner is a single line of code that does something useful and doesn't require any extra steps to compile or run.

You type one line, press enter, and get your result.

I first learned about one liners in Perl.

If we have a file.txt with the following content:

one two three four five

Here's a Perl one liner that counts the number of lines in a file:

bash $ perl -E '@l = <>; say scalar(@l)' < file.txt 5

The gist of YS

Ingy döt Net — Sun, 22 Jun 2025 00:00:00 +0000

Yesterday we started learning about the ys CLI and there's a lot more cool stuff to learn about it.

But today I want to switch it up and talk about one of my favorite programs that I use many times a day.

You probably know about GitHub gists. They are one of the best ways to share text files with others.

Let's take a look!

The `ys` Command

Ingy döt Net — Sat, 21 Jun 2025 00:00:00 +0000

There are different ways to use YS but the most common is to use it via the YS command-line tool: ys; a very versatile tool indeed.

There's a lot you can do with ys including using it like you would use jq or yq one-liners:

bash $ jq .bar < <(echo '{"foo": 123, "bar": 456, "baz": 789}') 456 $ yq .bar < <(echo -e 'foo: 123\nbar: 456\nbaz: 789') 456 $ ys .bar < <(echo -e 'foo: 123\nbar: 456\nbaz: 789') 456

Each of these tools have their own advantages and we'll be diving deep into those waters soon enough.

Today let's just start by exploring the basic things you can do with the ys CLI.

whens and lets

Ingy döt Net — Fri, 20 Jun 2025 00:00:00 +0000

Do you know how a YS assignment actually works?

It compiles into a Lisp let form.

Let's take a look...

More Fancier YS Conditionals

Ingy döt Net — Thu, 19 Jun 2025 00:00:00 +0000

Yesterday we looked at the cond and case functions.

The cond function has a couple cousins: condp and condf.

Let's take a look at them.

Fancier YS Conditionals

Ingy döt Net — Wed, 18 Jun 2025 00:00:00 +0000

Most languages support a case or switch construct which is a way to handle multiple conditions.

YS supports several similar but different constructs for this.

Today we'll focus on the cond and case functions.

When to when

Ingy döt Net — Tue, 17 Jun 2025 00:00:00 +0000

Yesterday we mentioned the when function as an alternative to if.

It might seem like a weaker form, so why would you use it?

It turns out that when is is really useful for a few reasons. You might end up using it more than if!

if - We Must

Ingy döt Net — Mon, 16 Jun 2025 00:00:00 +0000

Yesterday we talked about if being a special form.

It turns out that if is special in other ways. For instance, it requires both the then and else clauses to be present… but… it doesn't require the actual then and else keywords.

Today we'll finish our conversation about if and go over all the specifics.

if - You Are Special

Ingy döt Net — Sun, 15 Jun 2025 00:00:00 +0000

Yesterday I told you that if is a function.

I lied.

In reality, if is a "special form".

I'll explain special forms in a minute, but let's just say that they're "special"!

if - You Have to Ask!

Ingy döt Net — Sat, 14 Jun 2025 00:00:00 +0000

Today we're going to look at the if command.

In a functional language, if statements are a bit different.

They'll, well, um... Functions.

So what's the big deal?

YS Global Variables

Ingy döt Net — Fri, 13 Jun 2025 00:00:00 +0000

Last night a gave a talk about YS and YAML to the Toronto DevOps Meetup.

I had a lot of fun, and met a lot of great people.

Today I'm going to share one of the things I covered last night. Global variables.

It's not the most exciting topic, but it can be useful.

Using Environment Variables

Ingy döt Net — Thu, 12 Jun 2025 00:00:00 +0000

Tonight I'm giving a talk about YS and YAML to the Toronto DevOps Meetup.

What could be more important to a developer than environment variables?!

Let me show you how to use environment variables in YS and in your YAML files.

YS Multi Functions

Ingy döt Net — Wed, 11 Jun 2025 00:00:00 +0000

Many languages let you define functions with multiple signatures.

That is, you can have multiple functions with the same name but different arguments.

YS supports multi-arity functions. It dispatches on the number of arguments.

Let's see how it works.

Where the Funcs Have No Name

Ingy döt Net — Tue, 10 Jun 2025 00:00:00 +0000

Any self-respecting functional language has a way to create anonymous functions.

In YS there are more than one!

Today we'll talk about nameless functions, why they are useful, and how to create and call them.

Functionally Speaking

Ingy döt Net — Mon, 09 Jun 2025 00:00:00 +0000

YS is a functional programming language.

Therefore we should be able to write functions in YS.

This week I want to do a mini-series of blog posts about using and writing functions in YS.

Let's get started!

In The Beginning

Ingy döt Net — Sun, 08 Jun 2025 00:00:00 +0000

How did YAML get started in the first place?

Today's Sunday post is about YAML, not YS.

But since YS is YAML, I think that's OK.

This is the story of how the YAML data language got its start as far back as 1999.

!!! note "React and Comment here please!!!"

I'm not sure how many people are reading this series, but I'm enjoying
writing it.
It's nice to know that I'm not alone on this Summer journey.

I recently added Reactions and Comments support to these blog posts.
Scroll down to the bottom of each post to see them.

If you are enjoying the [**Summer of YS**](
http://0.0.0.0:8000/blog/category/summer-of-ys/) series, please don't forget
to react (and comment if you want to) to let me know!

TMTOWTDI for YS Expressions

Ingy döt Net — Sat, 07 Jun 2025 00:00:00 +0000

Like I said before, in YS, There's More Than One Way To Do It.

This is especially true for YS expressions.

Later on you'll learn that YS is a Lisp in disguise. In Lisp, an expression is a list consisting of a function and its arguments inside a set of parentheses.

Consider this Python code:

python name = "World" print("Hello, " + name + "!")

In a Lisp, this would be written as:

lisp (def name "World") (println (str "Hello, " name "!"))

In YS, this could be written as:

yaml name =: 'World' say: str('Hello, ' name '!')

I say could because... TMTOWTDI!

Today I'm going to show you many of the ways to DO IT in YS.

Loops and Strings

Ingy döt Net — Fri, 06 Jun 2025 00:00:00 +0000

Yesterday I left you with a program that really needed to "YS up"!

```bash $ ys -e ' url =: "https://github.com/dominictarr/random-name/raw/master/first-names.json"

people =: url.curl().json/load().shuffle().take(3) shoes =: read("shoes.yaml").yaml/load()

say: str(people.0, " wears size ", shoes.0.size, " ", join([shoes.0.name, "s"])) say: str(people.1, " wears size ", shoes.1.size, " ", join([shoes.1.name, "s"])) say: str(people.2, " wears size ", shoes.2.size, " ", join([shoes.2.name, "s"])) ' ```

Let's make this awesome!

YS Curling (up North)

Ingy döt Net — Thu, 05 Jun 2025 00:00:00 +0000

Ever been to Manitoba? I went there once when my flight from Seattle to Toronto diverted to Winnipeg because the plane's toilets stopped working! That's when I learned about the World's Largest Curling Rock.

!!! note "Toronto DevOps Meetup"

Speaking of Toronto, I'll be giving a talk called ["The YS way to YAML"](
https://www.meetup.com/toronto-enterprise-devops-user-group/events/307801910/)
at the Toronto DevOps Meetup on June 12th.
That's one week from today!

If you're in town I hope to see you there!

Today we'll be doing a little curling with YS.

Load and Compose your YAML Files

Ingy döt Net — Wed, 04 Jun 2025 00:00:00 +0000

Probably the biggest problem people have with YAML is that everything has to be in one file. Things start off nice and clean, but as requirements grow, so do your files!

What if you could compose your YAML documents like you compose your code? Lots of small, single-purpose, possibly reusable files that you can load and compose together into the thing you need?

That's what YS is all about. As you know, YS is a functional language, and it has quite a few ways to load data (and code too, since Code is Data™!) from external sources.

Today we'll be looking at how to load things from disk files, including:

Other YS files
YAML files (YAML is YS)
JSON files (JSON is YAML)

You can also load things from CSV/TSV files, shell commands, databases, APIs, environment variables, and the web, but those are topics for another day.

YS YAML Documents

Ingy döt Net — Tue, 03 Jun 2025 00:00:00 +0000

YAML files (aka YAML streams) can contain multiple "documents".

A YAML document is a top level mapping or sequence "node". Most YAML files contain a single document, but YAML files can contain multiple (or zero!) documents. New documents are started with a line of three dashes: ---.

YS can put these documents to all kinds of good use.

When you "load" a YAML file with YS, the result is the evaluation of the final document (by default). But since YS is functional, it can access any of the other documents.

Let's continue with yesterday's shoes example.

YAML Variables

Ingy döt Net — Mon, 02 Jun 2025 00:00:00 +0000

YAML itself isn't a functional programming language, but advanced users are probably aware of YAML's anchors, aliases and the merge key.

The merge key is YAML's one functional thing, and it's actually not even part of the YAML 1.2 spec. However, people find it useful and many YAML implementations (including YS) support it.

The merge key (<<) is a special key that allows you to merge the contents of one mapping into another.

Today we'll explore the merge key a bit and show how variables can make it nicer to use.

The Summer of YS

Ingy döt Net — Sun, 01 Jun 2025 00:00:00 +0000

Today starts a 3 month long, daily summertime journey into the intricacies of YAML and the wisdom of YS! Put on your favorite pair of coding sunglasses, grab a refreshing config drink, and let's get started!

Back in March I promised to start writing more often about all the ways that YS can help you out day-to-day with your YAML interactions. When I last posted here it was barely Spring and now Spring is turning into Summer.

Seasonal turning points be damned, I think of Summer as June, July, and August. In other words...

It's Summer dammit!

Let's declare this Summer, The Summer of YS!

Run a YAML File with Bash!

Ingy döt Net — Mon, 24 Mar 2025 00:00:00 +0000

Wait, what?!!?

Run a YAML file?

And with Bash?

How is that possible?

YAMLScript is YS!

Ingy döt Net — Mon, 10 Mar 2025 00:00:00 +0000

Greetings! And welcome back to YAMLScript in 2025!

Or as we now say, YS in '25!.

It's been a minute since our last update, but we've been working super hard to make YS the best it can be.

Oh… What's "YS", you say?

Well, don't say "Y-S"…

Say "Wise"!

The Kubernetes Effect

Ingy döt Net — Fri, 29 Nov 2024 00:00:00 +0000

In my many years of creating Open Source software and talking about it at conferences, some of the most productive development times are often those leading up to the presentation.

In the last post, I mentioned that I was going to present a 90 minute YS tutorial at KubeCon (November 15th in Salt Lake City).

The conference was amazing and the YS tutorial was a huge success. I came away with the feeling that YAML and YS had found their community. KubeCon felt like YAMLCon!

The Fall of YAMLScript!

Ingy döt Net — Sat, 05 Oct 2024 00:00:00 +0000

(or Exciting YS News for Fall 2024!)

Greetings!

It's been over 3 months since the last blog post here.

Just to be clear, the YS/YAMLScript project is alive and fantastic!

We've just been busy as hell on 2 very big things: Exercism and KubeCon.

To be successful in both of these endeavors, YS needed to be amazing both as a programming language (Exercism) and as a data language (KubeCon).

There's so much new stuff to talk about, and I promise to write about all of it after things get back to a normal pace.

Today let's talk about Exercism, KubeCon and the positive impacts they've had on YS.

Go Julia!

Ingy döt Net — Wed, 17 Jul 2024 00:00:00 +0000

Last week two new language bindings were added to the YS family: Go and Julia.

Dr. StrangeYAML or How I Learned to Stop Worrying and Love the LLM

Ingy döt Net — Thu, 20 Jun 2024 00:00:00 +0000

!!! quote ""

Well now, what happened is, uh, one of our data scientists, uh, well, he
went a little funny in the head.
You know.
Just a little funny.
And uh, he went and did a silly thing.

Well, I'll tell you what he did.
He started chatting with computers... in YAML.

Well, let me finish, Elon.

Let me *finish*, Elon.

Well, listen, how do you think *I* feel about it?

YS Spring Update

Ingy döt Net — Tue, 16 Apr 2024 00:00:00 +0000

It's been a while since I let you know what's been happening with YS. I've been busy working on it every day this year and I have a lot to tell you about!

YS Activity in 2024

Let me start by telling you about some of the events that have happened in the YS world recently.

Seajure Talk - I gave a talk at the Seajure (Seattle Clojure) Meetup in March.
YS Article - The New Stack published an article about YS in March
YS Podcast - I was interviewed on the "The REPL" by Daniel Compton in April.

Finally I'm presenting a talk about YS at the Open Source Summit North America this Thursday, April 18th. Super excited about that!

YS Firsts

Ingy döt Net — Thu, 14 Mar 2024 00:00:00 +0000

Remember Your First Time?

Do you remember the first time you wrote a program in a new language? For YS, mine was yesterday!

This is my first post of 2024. I've been working on YS non-stop since the last YS Advent 2023 post. Too busy to write a blog post, I guess.

Yesterday something awesome happened.

Putting out a YS release is a complicated process. It takes me about an hour to do it. Of course I plan to automate it fully but I just haven't had the tuits.

For the last several releases, I've had a text file that listed all the steps so that I wouldn't forget anything. Yesterday I automated that list...

...you guessed it...

...in YS!

Wrapped and Ready

Ingy döt Net — Sun, 24 Dec 2023 00:00:00 +0000

The Elves have everything wrapped up.

Literally!

Tonight's the big night.

It's Time to Deliver!

Perl to Rust

Ingy döt Net — Sat, 23 Dec 2023 00:00:00 +0000

When Santa is doing his job in the Luxembourg area, I've always wondered how he gets from Perl to Rust.

Maybe he takes this route!

Flip Flops

Ingy döt Net — Fri, 22 Dec 2023 00:00:00 +0000

Can you imagine Santa walking around in flip flops? I've never been up to the North Pole, but I'm pretty sure there's no beaches. I always pictured Santa wearing moon boots around the workshop.

YS on the other hand, is all about flip flops!

YAML, Python and the Holy Graal

Ingy döt Net — Thu, 21 Dec 2023 00:00:00 +0000

Which has a greater airspeed velocity... an unladen swallow or Santa's sleigh?

Well, that depends... are we talking about an African or European swallow?

Huh?

Godspeed

Ingy döt Net — Wed, 20 Dec 2023 00:00:00 +0000

I wonder if Santa has a Hemi? Supercharged, Turbocharged? Maybe a Nitro Burning Funny Sleigh? Dude's got to get around the world in one night. Godspeed, my festive friend!

Reindeer All The Way Down

Ingy döt Net — Tue, 19 Dec 2023 00:00:00 +0000

Santa is in charge of Christmas. He's the one who makes sure that all the children get presents. But who is in charge of getting Santa his presents? That's where the reindeer come in. They are the ones who make sure that Santa gets his presents. But who is in charge of getting the reindeer their presents? More reindeer! But who is in charge of getting the reindeer's reindeer their presents? More reindeer! It's reindeer all the way down.

Santa's in d'buggy

Ingy döt Net — Mon, 18 Dec 2023 00:00:00 +0000

With one week to go, Santa's gotta get his sleigh in top shape. Can't have any breakdowns on the big night. His sleigh might look like a simple wooden buggy, but it's more temperamental and buggy than a 2023 Tesla!

But this is Santa we're talking about. He's done this a few times, so he knows how to get the bugs out.

Rosetta Code

Ingy döt Net — Sun, 17 Dec 2023 00:00:00 +0000

How does Santa read all the signs in all the languages of the world? That's a lot of languages to know on top of all the other things he has to do. Luckily he has his trusty polyglot elf, Rosetta, at his side. Bet you didn't know that!

Let Lambda Come Over

Ingy döt Net — Sat, 16 Dec 2023 00:00:00 +0000

We know the names of Santa's reindeer: Dasher, Dancer, Prancer, Vixen, Comet, Cupid, Donner, Blitzen and Rudolph. And his elves: Alabaster Snowball, Bushy Evergreen, Pepper Minstix, Shinny Upatree, Sugarplum Mary, Wunorse Openslae, and the head elf, Bernard.

But we don't know the names of Santa's lambda reindeer and elves. Why would we? They are anonymous! They're also the hardest working of the bunch.

Naughty is Nice!

Ingy döt Net — Fri, 15 Dec 2023 00:00:00 +0000

As the architect of a major world holiday, Santa Claus has hard design choices to make. What is Suki going to get this year? He keeps it simple with the standard Naughty-Or-Nice algorithm.

As architects of an aspiring new programming language, the YS folks have design choices to make as well!

Naughty-Or-Nice should not be discounted but what about Naughty-And-Nice? Naughty-Xor-Nice???

My personal favorite?

Naughty-Is-Nice!!

Stocking Stuffers

Ingy döt Net — Thu, 14 Dec 2023 00:00:00 +0000

It's always nice to get a little something extra in your stocking whilst waiting for the big guy to show up on the big day.

Learning eveything you need to know about YS in 24 days is a tall order. I still have a quite a bit to learn about it myself! :-)

It helps to learn the small stuff first.

History Lesson

Ingy döt Net — Wed, 13 Dec 2023 00:00:00 +0000

Santa is Legend. Legends have histories. The histories of Santa are many and varied, some going back to the 4th century AD.

The history of YS is much shorter, but it's still a history. Today I'd like to tell you a little bit about it.

Future Proof

Ingy döt Net — Tue, 12 Dec 2023 00:00:00 +0000

Santa has very little margin for error. He has to get everything just right all in one night.

YS is a work in progress, and will be for a long time. I'm trying to get it right, but I'm no Santa! In fact I'm quite sure I'll get some things wrong. That's just the nature of the beast when you're a programmer.

Also, have you ever wondered why the magic YS starter tag has that /v0 at the end?

The YeS Express

Ingy döt Net — Mon, 11 Dec 2023 00:00:00 +0000

Santa's got a lot of ground to cover in a short amount of time. He doesn't have time to deal with confusing maps and directions.

Lisp has other-worldly powers of abstraction, but when it comes to reading syntax, most people prefer the familiarity of this world.

YS fully embraces all that Clojure has to offer, but syntax-wise it also offers a more familiar face.

States and Ladders

Ingy döt Net — Sun, 10 Dec 2023 00:00:00 +0000

Santa is a busy guy. He has a lot of work to do. He has to make a list and check it twice. He has to find out who's naughty and nice. He has the monumental task of transforming wishes into happiness.

YS only needs to transform YS code into Clojure code. But it's a bit more involved than you might think.

To make things easier the YS compiler breaks the transformation into eight distinct States and seven distinct ~~Ladders~~ transformations.

Coding with Style

Ingy döt Net — Sat, 09 Dec 2023 00:00:00 +0000

What's the best thing about Rudolph's nose? Is it that lights the way for Santa's sleigh? I'm calling BS on that. I'd say it's the main thing that gives the whole Sanata Story some Serious Style!

Good programmers do more than just get their solutions right. They do the whole thing with style. That makes the program easier to read, understand and maintain. It also gives the code a certain je ne sais quoi.

Going to the Library

Ingy döt Net — Fri, 08 Dec 2023 00:00:00 +0000

Programming in YS is as easy as reading a book. The only thing you really need is some good books! For that let's go to the library.

By books of course I mean YS functions. And by library I mean the YS Standard Library! There you'll find all-time best sellers like map, filter, reduce and say.

And Standard isn't the only Library in town...

Sharpen Your Tools

Ingy döt Net — Thu, 07 Dec 2023 00:00:00 +0000

Wanna make some fun toys with YS? You'll need some sharp tools. You think those elves make all those toys with dull tools?

The CLI tool ys is the main tool you'll use to work with YS. Today we'll learn about all the things you can do with it.

Modes of Transportation

Ingy döt Net — Wed, 06 Dec 2023 00:00:00 +0000

How do you get around? Some people walk, some ride bikes, some drive cars (or the cars drive them), some take trains, some in planes, so many ways, even some in sleighs.

In YS, data gets around via various modes of transportation... 3 modes to be exact.

Rememeber back on December 3rd when we talked about the 2 different states that a YS program can be in? In one state say is a function, and in the other it's just a plain string.

We call these states "modes", and there is actually three of them.

Unwrapping Gifts

Ingy döt Net — Tue, 05 Dec 2023 00:00:00 +0000

It's certainly a relief now that I've told you the big secret about YS. Now that you know that YS is really Clojure, I don't have to dance around the subject anymore. I didn't want to scare you away by going Full-Lisp on you from the start!

Now we can just get into it. We can write, run and load YS until the cows come home.

But wait... How do we do that? You don't even have YS installed yet!

Santa's Big Secret

Ingy döt Net — Mon, 04 Dec 2023 00:00:00 +0000

I've got a little secret to tell you. I've been hiding a little something from you. Even that's a lie. I've actually been hiding something very very big something from you.

*** YS is a Lisp! *****

Load em Up!

Ingy döt Net — Sun, 03 Dec 2023 00:00:00 +0000

On the 3rd day of Advent, my YS code gave to me...
A sequence in a map tree!

Did you know that all JSON is YAML? You should, because I told you that yesterday!

It's true. YAML is a superset of JSON. Both in terms of syntax and data model.

This means that any possible valid JSON input is also valid as a YAML input. A proper YAML loader and a JSON loader should produce the same data structure from the same JSON input.

!!! note

Assuming a YAML 1.2 loader using the YAML 1.2 JSON Schema

Twas a Bit

Ingy döt Net — Sat, 02 Dec 2023 00:00:00 +0000

!!! quote

'Twas a bit before Hanukkah, and all through the igloo,  
not a creature was stirring, not even a frog.  
The stockings were hung by the window with care,  
In hopes that St. Krampus soon would be there.  
The offspring were nestled all snug in their bunks,  
While visions of spicy-cookies danced in their heads.  
And cuz in their 'kerchief, and I in my bonnet,  
Had just settled down for a long winter's snooze.  
When out on the lawn there arose such a clatter,  
I sprang from my bench to see what was the matter.  
Away to the window, I flew like a jet,  
Tore open the shutters and threw up the curtain.  
The asteroid on the breast of the new-fallen frost,  
Gave the lustre of mid-day to dirt below.  
When what to my wondering eyes should materialize?  
But a miniature car, and eight tiny elephants.

Well that was a bit weird. Let's try again. Don't worry, it's not that hard to write Winter holiday poetry when you have YS on your side!

YS Advent 2023

Ingy döt Net — Fri, 01 Dec 2023 00:00:00 +0000

Seasons Greetings, my YAML friends!

What if I told you that you could write a program in YAML that would generate a Christmas tree?

Well, you can! Here's how:

Welcome to the YS Blog

Thu, 26 Oct 2023 00:00:00 +0000

Greetings!

Welcome to the YS blog.

This is where we will introduce you to novel concepts about YS as the language evolves.