CodeGenerator.prototype.generateFunctionParams = function()

in escodegen.js [889:929]


    CodeGenerator.prototype.generateFunctionParams = function (node) {
        var i, iz, result, hasDefault;

        hasDefault = false;

        if (node.type === Syntax.ArrowFunctionExpression &&
                !node.rest && (!node.defaults || node.defaults.length === 0) &&
                node.params.length === 1 && node.params[0].type === Syntax.Identifier) {
            // arg => { } case
            result = [generateAsyncPrefix(node, true), generateIdentifier(node.params[0])];
        } else {
            result = node.type === Syntax.ArrowFunctionExpression ? [generateAsyncPrefix(node, false)] : [];
            result.push('(');
            if (node.defaults) {
                hasDefault = true;
            }
            for (i = 0, iz = node.params.length; i < iz; ++i) {
                if (hasDefault && node.defaults[i]) {
                    // Handle default values.
                    result.push(this.generateAssignment(node.params[i], node.defaults[i], '=', Precedence.Assignment, E_TTT));
                } else {
                    result.push(this.generatePattern(node.params[i], Precedence.Assignment, E_TTT));
                }
                if (i + 1 < iz) {
                    result.push(',' + space);
                }
            }

            if (node.rest) {
                if (node.params.length) {
                    result.push(',' + space);
                }
                result.push('...');
                result.push(generateIdentifier(node.rest));
            }

            result.push(')');
        }

        return result;
    };