Attributes are key-value pairs that configure elements and provide metadata.

Syntax

Attribute syntax uses key-value pairs separated by semicolons and/or newlines:

(
    key1: value1;
    key2: value2
    key3: value3
)

Data Types

Attributes can have different data types that define what values they can contain and how they are validated. Chalk supports both built-in primitive data types and custom data types defined in your library.

Primitive Types

• string: Text values (no quotes needed)
• number: Numeric values, including decimals
• boolean: True/false values (accepts: true/false, yes/no, 1/0)
• string-list: Comma-separated strings
• number-list: Comma-separated numbers
• formatted-string: Text with markdown formatting support

Examples

element(
    title: My Title
    count: 42
    enabled: true
    tags: javascript,react,frontend
    description: This supports **bold** and *italic* text
)

Custom Types

Libraries can define custom attribute types with validation:

const dateType = {
  identifier: 'date',
  validate: (value) => /^\d{4}-\d{2}-\d{2}$/.test(value)
};

Attribute Validation

• Required vs Optional: Attributes can be marked as required or optional
• Default Values: Optional attributes can have default values
• Type Validation: Values are validated against their declared types

Next Steps

• Language Guide - Back to language guide index
• Elements Reference - Learn about different element types
• Formatting Guide - Inline text formatting
• Primitives Guide - Built-in elements and formatting
• Language Overview - File types and basic syntax
• API Documentation - How to define attributes in libraries
• Home - Back to documentation home