How to represent key-value pairs in YAML

Overview

YAML is a human-friendly data serialization standard for all programming languages. In YAML, key-value pairs are one of the core constructs and can be used to represent any type of data, including lists and hashes.

What is a key-value pair?

A key-value pair is a simple data structure that consists of a unique identifier (the key) and the corresponding value of that identifier.

The key can be any type of data, such as a text string or an integer. The value can also be of any type of data, including string, integer, float, boolean, list, or even other key-value pairs.

%0 node_0 Key node_0_1 Value node_0->node_0_1
A key-value pair

Uses of a key-value pair

Here are some of the most common uses of key-value pairs:

  • They are used in the implementation of hash tables, whereby they are used to store and retrieve information.

  • Many programming languages include built-in support for key-value pairs as a core data structure, making them a fundamental part of many software applications.

Overall, key-value pairs provide a powerful and flexible way to store and work with data.

Syntax

In YAML, key-value pairs are represented using a colon (:), followed by the content of the value. The basic format of a key-value pair is as follows:

key: value

Where key represents the key, and value represents the corresponding value.

Example

For example, let's say we have the data as is shown below:

Employee Data

Name

Age

Occupation

John Doe

43

Software Engineer

We can represent this in YAML using key-value pairs as follows:

name: John Doe
age: 43
occupation: Software Engineer

As we can see, the format is very simple. Each key is followed by a colon and then the value. We can also use quotation marks (' or ") around the key-value pair if we want to include special characters or whitespace.

Conclusion

In this Answer, we learned how to represent key-value pairs in YAML. We also saw a simple example of how we can use this data serialization standard.

There are many other features available in YAML that can be used to represent key-value pairs and other data structures. Whether we are working with a simple key-value pair or something more complex, YAML offers flexibility and power for representing structured data.

If you want to learn more about the use of YAML to represent key-value pairs and other data structures, you can check out the Introduction to YAML course for more information.

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