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YAML Basics

YAML (YAML Ain't Markup Language) is a human-readable data serialization format. It is often used for configuration files, data exchange between languages with different data structures, and in applications where data is being stored or transmitted.

Indentation and Structure​

YAML uses indentation to represent the structure of data. Spaces are preferred over tabs, and indentation should be consistent. It uses colons and dashes to denote key-value pairs and lists.

Key-Value Pairs​

Key-value pairs are used to represent data. The key and value are separated by a colon, with a space after the colon. For example:

name: John Doe
age: 30

Lists​

Lists or arrays are represented using a hyphen followed by a space, and items in the list are indented. For example:

- item 1
- item 2
- item 3

Nested Structures​

You can nest data structures within YAML, including dictionaries within dictionaries and lists within dictionaries. Maintain consistent indentation for nested structures.

person:
  name: John Doe
  age: 30
  hobbies:
    - Reading
    - Swimming

Comments​

YAML supports comments. Comments begin with the # symbol, and everything to the right of it is treated as a comment.

# This is a comment
key: value

Multiline Strings​

You can represent multiline strings using the | character for a literal block style. This preserves line breaks and indentation.

description: |
  This is a multiline
  string in YAML.

Quoted Strings​

If your string contains characters that could be interpreted as a YAML indicator (e.g., :, -, #), you can enclose the string in double or single quotes.

message: "This is a string with a colon: it's inside quotes."