Method constructor

contributed/jsonparser/jsonparser.js:156–163

(options)

    // The VPT class constructor initializes with an optional matcher or patterns, always invoking 'begin' for the matcher and only for patterns matching the root pattern.
    // Note: Instances of VPT with a matcher or patterns cannot be shared; VPT constructor must execute for each new parser.
    constructor(options) {
        if (options === undefined)
            throw new Error("invalid options");
        this.node = this.makeNode(NodeType.root);
        this.matcher = options.matcher;
        this.patterns = options.patterns;
        this.doEvent("onBegin");
    }

    // Execute 'matcher events' unconditionally and 'pattern events' selectively when nodes match a pattern.
    doEvent(event) {