readOptionalMacroArgument

How to read this API

These are TypeScript APIs compiled into SnapTeX; a .tex project cannot load them at runtime.

• function name(...) is a helper that your rule imports and calls.
• apply(...), render(...), extract(...), and collect(...) are callbacks that your rule implements and SnapTeX calls.
• renderer.name(...), context.name(...), input.name(...), and deps.name(...) are methods SnapTeX supplies to callbacks; do not import or construct them.
• service.name(...) is an instance method called after your host or test constructs PreviewUpdateService.

Register extension declarations through SNAP_TEX_RULES in src/rules.ts. See Source API Scope for imports, value ownership, output safety, rebuilds, and testing.

Reads an argument attached to an AST macro whose opening delimiter is [. Use it when the parser is known to attach the command arguments; it does not scan sibling nodes.

Signature

function readOptionalMacroArgument(
    node: SnaptexAstMacro,
    index = 0
): SnaptexAstArgument | undefined

Returns

The indexed attached optional argument or undefined. Detached sibling brackets are not searched.

Call relationships

• Called by: readAstCommandArguments and direct AST rules.
• Often followed by: argumentText.

const shortTitle = argumentText(readOptionalMacroArgument(node));

See also

• readRequiredMacroArgument
• readAstCommandArguments