YAML syntax

Following is an introduction to the YAML syntax. If you are familiar with YAML, skip to the TYPO3 specific information:

• YamlFileLoader

See also

A good general introduction to YAML syntax, basic data types, etc.:

• “YAML Syntax” in Grav documentation

The TYPO3 coding guidelines for YAML define some basic rules to be used in the TYPO3 core and extensions. Additionally, yaml has general syntax rules.

• File ending .yaml
• Indenting with 2 spaces (not tabs). Spaces MUST be used. You MUST use the correct indenting level.
• Use UTF-8
• All text is case-sensitive
• Enclose strings with single quotes (‘’)

Important

The following MUST be adhered to in order to produce valid syntax:

1. Use spaces, not tabs to indent
2. Identing is not optional. It is used to define the hierarchy of the data

To get a better understanding of YAML, you might want to compare YAML with PHP arrays:

PHP:

$a = [
    'key1' => 'value',
    'key2' => [
        'key2_1' => 'value'
];

$b = [
    'apples',
    'oranges',
    'bananas'
];

YAML:

# mapping (key / value pairs)
a:
  key1: 'value'
  key2:
    key2_1: 'value'

# sequence (list)
b:
  - 'apples'
  - 'oranges'
  - 'bananas'