YAML

Yaml is a highly readable configuration file format. It’s closely tied with json and XML, being directly convertible to both. Much like python, yaml’s claim to fame is extreme legibility by leveraging white space as syntax. Unlike python, this is very appropriate for configuration files

Here’s a sample that covers much of yaml’s syntax:

my_key: my value
my_num: 8
my_arr: [

one:
 - two
 - three

Background

If yaml is so great, why isn’t it always used? The problem lies in its awful implementations

Syntax

Maps

Arrays

Multi-line Strings

Yaml has way too many ways to do multi-line strings, trying to fit every niche case. Luckily, we only really need to remember 3

One line

For a really long string that you just want on one line, use

key: >
    my string starts here
    and still goes on
    all on the same line

Multiple lines

If you want a string over multiple lines, notable useful for formatted text, the following will preserve the visual line breaks. Indenting is determined by the indent of the first line, and white space to the left will be stripped

key: |
    a yaml line starts
    with line breaks preserved

Anything more complicated

Just use javascript-style multi-line strings. \ at the end will escape all the white space until the next character. \n creates a linebreak. \" allows you to use quotes within the string itself

key: "
    my string starts here\n