
Various types of characters are used for various functionalities. This chapter talks in detail about syntax used in YAML and focuses on character manipulation.
Indicator characters include a special semantics used to describe the content of YAML document. The following table shows this in detail.
| Sr.No. | Character & Functionality |
|---|---|
| 1 | _ It denotes a block sequence entry |
| 2 | ? It denotes a mapping key |
| 3 | : It denotes a mapping value |
| 4 | , It denotes flow collection entry |
| 5 | [ It starts a flow sequence |
| 6 | ] It ends a flow sequence |
| 7 | { It starts a flow mapping |
| 8 | } It ends a flow mapping |
| 9 | # It denotes the comments |
| 10 | & It denotes node’s anchor property |
| 11 | * It denotes alias node |
| 12 | ! It denotes node’s tag |
| 13 | | It denotes a literal block scalar |
| 14 | > It denotes a folded block scalar |
| 15 | ` Single quote surrounds a quoted flow scalar |
| 16 | " Double quote surrounds double quoted flow scalar |
| 17 | % It denotes the directive used |
The following example shows the characters used in syntax −
%YAML 1.1
---
!!map {
? !!str "sequence"
: !!seq [
!!str "one", !!str "two"
],
? !!str "mapping"
: !!map {
? !!str "sky" : !!str "blue",
? !!str "sea" : !!str "green",
}
}
# This represents
# only comments.
---
!!map1 {
? !!str "anchored"
: !local &A1 "value",
? !!str "alias"
: *A1,
}
!!str "text"