YAML - Basics

Now that you have an idea about YAML and its features, let us learn its basics with syntax and other operations. Remember that YAML includes a human readable structured format.

Rules for Creating YAML file

When you are creating a file in YAML, you should remember the following basic rules −

YAML is case sensitive

The files should have .yaml as the extension

YAML does not allow the use of tabs while creating YAML files; spaces are allowed instead

Basic Components of YAML File

The basic components of YAML are described below −

Conventional Block Format

This block format uses hyphen+space to begin a new item in a specified pst. Observe the example shown below −

--- # Favorite movies
 - Casablanca
 - North by Northwest
 - The Man Who Wasn t There

Inpne Format

Inpne format is depmited with comma and space and the items are enclosed in JSON. Observe the example shown below −

--- # Shopping pst
   [milk, groceries, eggs, juice, fruits]

Folded Text

Folded text converts newpnes to spaces and removes the leading whitespace. Observe the example shown below −

- {name: John Smith, age: 33}
- name: Mary Smith
  age: 27

The structure which follows all the basic conventions of YAML is shown below −

men: [John Smith, Bill Jones]
women:
  - Mary Smith
  - Susan Wilpams

Synopsis of YAML Basic Elements

The synopsis of YAML basic elements is given here: Comments in YAML begins with the (#) character.

Comments must be separated from other tokens by whitespaces.

Indentation of whitespace is used to denote structure.

Tabs are not included as indentation for YAML files.

List members are denoted by a leading hyphen (-).

List members are enclosed in square brackets and separated by commas.

Associative arrays are represented using colon ( : ) in the format of key value pair. They are enclosed in curly braces {}.

Multiple documents with single streams are separated with 3 hyphens (---).

Repeated nodes in each file are initially denoted by an ampersand (&) and by an asterisk (*) mark later.

YAML always requires colons and commas used as pst separators followed by space with scalar values.

Nodes should be labelled with an exclamation mark (!) or double exclamation mark (!!), followed by string which can be expanded into an URI or URL.