// "foreach: someExpression" is equivalent to "template: { foreach: someExpression }" // "foreach: { data: someExpression, afterAdd: myfn }" is equivalent to "template: { foreach: someExpression, afterAdd: myfn }" ko.bindingHandlers['foreach'] = { makeTemplateValueAccessor: valueAccessor => { return () => { var modelValue = valueAccessor(), // Unwrap without setting a dependency here unwrappedValue = ko.isObservable(modelValue) ? modelValue.peek() : modelValue; // If unwrappedValue is the array, pass in the wrapped value on its own // The value will be unwrapped and tracked within the template binding // (See https://github.com/SteveSanderson/knockout/issues/523) if ((!unwrappedValue) || typeof unwrappedValue.length == "number") return { 'foreach': modelValue }; // If unwrappedValue.data is the array, preserve all relevant options and unwrap again value so we get updates ko.utils.unwrapObservable(modelValue); return { 'foreach': unwrappedValue['data'], 'as': unwrappedValue['as'], 'beforeRemove': unwrappedValue['beforeRemove'] }; }; }, 'init': (element, valueAccessor) => ko.bindingHandlers['template']['init'](element, ko.bindingHandlers['foreach'].makeTemplateValueAccessor(valueAccessor)) , 'update': (element, valueAccessor, allBindings, viewModel, bindingContext) => ko.bindingHandlers['template']['update'](element, ko.bindingHandlers['foreach'].makeTemplateValueAccessor(valueAccessor), allBindings, viewModel, bindingContext) }; ko.expressionRewriting.bindingRewriteValidators['foreach'] = false; // Can't rewrite control flow bindings ko.virtualElements.allowedBindings['foreach'] = true;