Function parseFunction

lib/filbert.js:2407–2638

(node)

  }

  function parseFunction(node) {
    // TODO: The node creation utilities used here are tightly coupled (e.g. variable names)

    var suffix = newAstIdCount++;
    node.id = parseIdent();
    node.params = [];

    // Parse parameters

    var formals = [];     // In order, maybe with default value
    var argsId = null;    // *args
    var kwargsId = null;  // **kwargs
    var defaultsFound = false;
    var first = true;

    scope.startFn(node.id.name);

    expect(_parenL);
    while (!eat(_parenR)) {
      if (!first) expect(_comma); else first = false;
      if (tokVal === '*') {
        if (kwargsId) raise(tokPos, "invalid syntax");
        next(); argsId = parseIdent();
      } else if (tokVal === '**') {
        next(); kwargsId = parseIdent();
      } else {
        if (kwargsId) raise(tokPos, "invalid syntax");
        var paramId = parseIdent();
        if (eat(_eq)) {
          formals.push({ id: paramId, expr: parseExprOps(false) });
          defaultsFound = true;
        } else {
          if (defaultsFound) raise(tokPos, "non-default argument follows default argument");
          if (argsId) raise(tokPos, "missing required keyword-only argument");
          formals.push({ id: paramId, expr: null });
        }
        scope.addVar(paramId.name);
      }
    }
    expect(_colon);

    // Start a new scope with regard to the `inFunction`
    // flag (restore them to their old value afterwards).
    // `inFunction` used to throw syntax error for stray `return`
    var oldInFunc = inFunction = true;

    // If class method, remove class instance var from params and save for 'this' replacement
    if (scope.isParentClass()) {
      var selfId = formals.shift();
      scope.setThisReplace(selfId.id.name);
    }

    var body = parseSuite();
    node.body = nc.createNodeSpan(body, body, "BlockStatement", { body: [] });

    // Add runtime parameter processing
    // The caller may pass a complex parameter object as a single parameter like this:
    // {formals:[<expr>, <expr>, ...], keywords:{<id>:<expr>, <id>:<expr>, ...}}