YAML¶

YAML (YAML Ain’t Markup Language) is a human-readable data serialization language. In the Clover2, it is used to describe ArUco marker maps, camera configs, and system parameters.

Basic Syntax Rules¶

Key-value pairs: key: value (a space must always follow the colon)

Comments: # — everything following the # on a line is ignored

  name: test          # this is an inline comment
  # this is a standalone comment line

YAML does not support block comments (/* */). You can place a comment at the end of a line or on a standalone line.

Indentation: Use spaces for indentation (2 or 4). Do not use tabs.
Strings: You cany write strings without quotes. If a value contains special characters or could be interpreted as another YAML data type, use double " " or single ' ' quotes.
Numbers: Write integers and decimal numbers without quotes: 42, 3.14, -1.5, 1e-3
Booleans: true / false, yes / no, on / off
Null values: ~, null, or an empty field
Lists (block style): Each list item starts with - (dash + space):
```
markers:
  - id: 0
  - id: 1
```

Lists (inline style): You can write list items in square brackets separated by commas:

markers: [{id: 0, size: 0.3}, {id: 1, size: 0.3}]
# or
markers: [0, 1, 2, 3]

List of dictionaries (explicit block style):

markers:
  - {id: 0, size: 0.3, x: 1.0, y: 2.0}
  - {id: 1, size: 0.3, x: 3.0, y: 4.0}

Here markers contains two dictionaries. Each dictionary describes one marker and contains its id, size, x, and y.

Multiline keyless arrays:
```
ids:
  - 10
  - 20
  - 30
```
Dictionaries (nested): Indentation defines nesting levels:
```
pose:
  x: 1.0
  y: 2.0
```
Dictionaries (inline style): Several key-value pairs can be written in curly braces separated by commas:
```
pose: {x: 1.0, y: 2.0, z: 0.5}
```

Note

Indentation must be consistent. If the first level uses 2 spaces, all subsequent levels must use 2 spaces. Indentation determines the structure of the YAML file. Incorrect indentation can cause a parsing error.