YAML_Ansible_2

 

Types of YAML Strings

YAML supports 4 main styles:

🟢 1. Plain Strings (No quotes)

🟡 2. Single-Quoted Strings ' '

🔵 3. Double-Quoted Strings " "

🟣 4. Multi-line Strings (VERY IMPORTANT 🔥)

🟢 1. Plain Strings (No quotes)

name: Alagarasan

role: DevOps Engineer

company: TCS

🟢 2. Double-Quoted Strings

message: "Start\nEnd" # \n is treated as a newline character

👉 Output

Start

End

quote: "He said, \"YAML is easy\"". # \" is treated as a literal double quote or \" lets you escape double quotes

👉 Output

He said, "YAML is easy"

tab: "Hello\tDevOps" # \t is treated as a tab character

quote: "He said \"Hi\"" # \" is treated as a literal double quote

path: "C:\\Program Files\\App"

👉 Output

C:\Program Files\App

💡 Why?

\ is a special character → must escape as \\

Prevent Boolean Conversion

value: "yes"

👉 Output

yes (string)

Tabs / Formatting # \t = tab spacing

text: "Name:\tAlagarasan"

👉 Output

Name: Alagarasan

Multi-line Formatting (Inline)

msg: "Line1\nLine2\nLine3"

👉 Output

Line1

Line2

Line3

🟢 3. Single-Quoted Strings # Everything is treated literally,No special character processing

In YAML, single-quoted strings (' ') are used when you want the content to be taken literally — no escape sequences, no special processing.

name: 'Alagarasan'

city: 'Chennai'

✔ Everything inside ' ' is treated as plain text.

Special Characters (No escaping needed)

path: '/usr/local/bin'

message: 'Hello: World!'

✔ Characters like :, /, ! are safe inside single quotes.

Quotes Inside String

To include a single quote inside, double it ('')

text: 'It''s DevOps'

👉 Output: It's DevOps. # Only one escape:

No Escape Sequences

newline: 'Line1\nLine2'

👉 Output (literal, NOT new line):

Line1\nLine2

❌ \n is NOT interpreted

✔ It stays as plain text

admin: 'true'

🔍 What’s happening here?

In YAML, certain words are reserved keywords (called boolean values):

true, false

yes, no

on, off

If you write:

admin: true

👉 YAML interprets it as a boolean, not a string.

🧠 Why use single quotes?

When you write:

admin: 'true'

👉 Now YAML treats it as a string, not a boolean.

Value written YAML interprets as

true Boolean true

'true' String "true"

"true" String "true"

admin: 'true' # string

enabled: true # boolean

Leading / Trailing Spaces Preserved

value: ' hello '

👉 Output:

" hello "

When to Use Single Quotes

Use ' ' when:

You want literal values

You don’t need escape sequences

String contains special characters like :, #, !

You want safe, predictable parsing

🟣 4. Multi-line Strings (VERY IMPORTANT 🔥)

Literal block (|) → preserves format

message: |

Hello

DevOps

Team

👉 Output:

Hello

DevOps

Team

Folded block (>) → merges lines

message: >

Hello

DevOps

Team

👉 Output:

Hello DevOps Team