SML Textbook · SML { ❄ } — SNOWARE Markup Language

SML Textbook{ ❄ }

Welcome to the official textbook of SML (SNOWARE Markup Language).

This is a progressive and beginner oriented textbook, which can also be used as a reference book for reading at any time. Whether or not you have used JSON/YAML/TOML, you can learn to write configurations and describe data using SML from scratch.

One sentence understanding of SML: It is a declarative data/configuration format that writes configurations like notes - quotation marks can be omitted, commas can be omitted, and the structure is delimited by curly braces {}.

How to read this book

-Zero Foundation: Starting from Chapter 1, read one chapter after another, with each chapter having a “hands-on try”.

-Experienced: Skip directly to chapters 4-5 to see advanced abilities such as include/contract.

-Check usage: Use the following table of contents to jump to the corresponding chapter, or read the “Comparison Table/Error Troubleshooting” in the appendix.

Chapter	Theme	You will learn
Preface	Why SML	What problem does it solve and the difference between it and JSON/YAML
Chapter 1	First SML file	Key value pairs, comments, scalar types (string/number/pool/null)
Chapter 2	Blocks and Nests	Object Blocks, Arrays, Colons Can Be Saved, Nested Structures
Chapter 3	Fragment Inheritance	`@base` Definition, `&base` Reference, Configuration Reuse
Chapter 4	Include and namespace	Split files, `as ns` isolation, `import` alias, partial import (`as ns { a, b }` / `{ a, b } as ns in "f"`)

Chapter

Theme

You will learn

Preface

Why SML

What problem does it solve and the difference between it and JSON/YAML

Chapter 1

First SML file

Key value pairs, comments, scalar types (string/number/pool/null)

Chapter 2

Blocks and Nests

Object Blocks, Arrays, Colons Can Be Saved, Nested Structures

Chapter 3

Fragment Inheritance

@base Definition, &base Reference, Configuration Reuse

Chapter 4

Include and namespace

Split files, as ns isolation, import alias, partial import (as ns { a, b } / { a, b } as ns in "f")

Agreement

-The code block labeled sml is the SML source code; The annotations rust/js/c/lua are host language calls.

-In the example, #, --, and // are all comments, which can be written in any way.

Hands on practice

After reading this chapter, directly modify SML in the editor below and click “Run” to immediately see the parsing results or validation errors - having output is necessary for efficient learning.

✍ Hands-on exercise Write an SML configuration that includes name (string gateway), port (integer 8080), debug (boolean true), tags (array containing logging and metrics). After finishing writing, click on 'Verify' and then look at the parsing results.

💡 Hint: Try changing the port to "8080" (in quotation marks), and the verification will tell you that it is not an integer 8080.

name: gateway
port: 8080
debug: true
tags: [ logging metrics ]

SML Textbook{ ❄ }

How to read this book

Agreement

Hands on practice

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