i try make editor that allow user attach function to dynamic objects
each object have init method, allow user attach some actions on user input
think about this
user select baby and write in textarea
move(1)
then select tank and insert in text area
onEnter(){
fire(1)
}
we have baby and tank and some other dynamic objects
i pass code from text area to each object initActions function
Baby{
move(number){
//some action here...
}
initActions(code){
this.init = Function(code)
this.init()
}
that cause this error
ReferenceError: move is not defined
in baby object initActions
how can i make move available from parent object in function call
someone answered me on irc channel
evalWith(target, code) {
const keys = [], values = [];
for (let o = target; o; o = Object.getPrototypeOf(o))
for (const key of Object.getOwnPropertyNames(o)) {
//console.log(o, key)
try{
let value = target[key];
if (typeof value === "function")
value = value.bind(target);
keys.push(key);
values.push(value);
}catch(e){
//console.log(o,key)
}
}
return Function(keys, code).apply(null, values);
}
Related
This program is reading through the nested object searching for a specific key & values. Once this data is found it has to initiate callback to send back the data. The object looks like this:
{
"name": "joel",
"title": "CTO",
"edu": {
"school": "RMB",
"college": "GNK",
"pg": "CDAC",
"extract": "This is a large text ..."
}
}
Here as I come from synchronous programming background I am not able to understand when I have to initiate the callback and also ensure variables are in scope
function parseData(str, callback) {
function recursiveFunction(obj) {
var keysArray = Object.keys(obj);
for (var i = 0; i < keysArray.length; i++) {
var key = keysArray[i];
var value = obj[key];
if (value === Object(value)) {
recursiveFunction(value);
}
else {
if (key == 'title') {
var title = value;
}
if (key == 'extract') {
var extract = value.replace(/(\r\n|\n|\r)/gm," ");
callback(null, JSON.stringify({title: title, text: extract}));
}
}
}
}
recursiveFunction(str, callback(null, JSON.stringify({title: title, text: extract})));
};
when this code is executed we get following error
/parseData.js:29
recursiveFunction(str, callback(null, JSON.stringify({title: title, text: extract})));
^
ReferenceError: title is not defined
Okay. So you want a function that retrieves the first property named title and the first property named extract from a nested object, no matter how deeply nested these properties are.
"Extract a property value from an object" is basically is a task in its own right, we could write a function for it.
There are three cases to handle:
The argument is not an object - return undefined
The argument contains the key in question - return the associated value
Otherwise, recurse into the object and repeat steps 1 and 2 - return according result
It could look like this:
function pluck(obj, searchKey) {
var val;
if (!obj || typeof obj !== "object") return;
if (obj.hasOwnProperty(searchKey)) return obj[searchKey];
Object.keys(obj).forEach(function (key) {
if (val) return;
val = pluck(obj[key], searchKey);
});
return val;
}
Now we can call pluck() on any object and with any key and it will return to us the first value it finds anywhere in the object.
Now the rest of your task becomes very easy:
var obj = {
"name": "joel",
"title": "CTO",
"edu": {
"school": "RMB",
"college": "GNK",
"pg": "CDAC",
"extract": "This is a large text ..."
}
}
var data = {
title: pluck(obj, "title"),
text: pluck(obj, "extract")
};
This function that you 've posted above has nothing to do with async programming. I will respond in the context of the chunk of code that you 've posted. The error that you have is because you are calling the recursiveFunction(str, callback(null, JSON.stringify({title: title, text: extract}))); but the title variable is nowhere defined. I can see a definition of the title but it is in the the context of the recursiveFunction function. The variables that you define in there are not visible outside of the scope of that function and that's why you have this error.
You are trying to do something strange in this line:
recursiveFunction(str, callback(null, JSON.stringify({title: title, text: extract})));
This line will invoke the callback and will pass in the recursiveFunction the results of this function. I would expect to see something like that in this line:
recursiveFunction(str, callback);
OK, we all know this works:
vm.myObject = {
required : "This field requires data",
.....
}
But how can I create that same object dynamically when the property 'keys' and 'values' come from a json file, eg:
json:
[
{ "key" :"required", "value": "This field requires data"},
.....
]
service:
var myObject = {}
DynamicObjSvc.get()
.success(function(data){
data.forEach(function(item){
// pass each key as an object property
// and pass its respective value
?????????
})
.....
UPDATE:
Kavemen was mostly correct, this turned out to be the solution:
var myObject = {};
DynamicObjSvc.all()
.success(function(data){
angular.forEach(data, function(msg) {
myObject[msg.key] = msg.value; <-- his answer was incorrect here
});
$fgConfigProviderRef.validation.message(myObject);
})
.error(function(err){
console.log(err.message);
})
You can use angular.forEach and the bracket notation for setting (and getting) object properties in Javascript
var myObject = {}
DynamicObjSvc.get().success(
function(data) {
angular.forEach(data, function(value, key) {
myObject[key] = value;
});
}
);
See also Working with Objects from MDN
EDIT
I see now that your data is really an array of objects, not just a single object, so yes, the code above could lead you astray.
In any case, the method of setting an object's properties dynamically using the bracket notation is sound; the loop could be reworked to handle your data array as such:
//we have an array of objects now
var myObjects = [];
DynamicObjSvc.get().success(
function(data) {
//for each object in the data array
for(var i = 0; i < data.length; i++) {
//create and populate a new object for the ith data element
var newObject = {};
angular.forEach(data[i], function(value, key) {
newObject[key] = value;
});
//and add it to the overall collection
myObjects.push(newObject);
}
}
);
I know that it is possible to create an instance from a symbol like is shown in this link:
Create an instance of an object from a String in Dart?
But this doesn't work for me since what I want to do is create an instance without having the class.
This problem is caused because I have One class with an internal List:
class MyNestedClass {
String name;
}
class MyClass {
int i, j;
String greeting;
List<MyNestedClass> myNestedClassList;
}
And I want to convert a map to this class:
{
"greeting": "hello, there",
"i": 3,
"j": 5,
"myNestedClassList": [
{
"name": "someName1"
},{
"name": "someName2"
}
]
}
right now I am doing something like this:
static void jsonToObject(String jsonString, Object object) {
Map jsonMap = JSON.decode(jsonString); //Convert the String to a map
mapToObject(jsonMap, object); //Convert the map to a Object
}
static void mapToObject(Map jsonMap, Object object) {
InstanceMirror im = reflect(object); //get the InstanceMirror of the object
ClassMirror cm = im.type; //get the classMirror of the object
jsonMap.forEach((fieldNameStr, fieldValue) { // For each element in the jsonMap
var fieldName = new Symbol(fieldNameStr); // convert the fieldName in the Map to String
if (isPrimitive(fieldValue)) { // if fieldValue is primitive (num, string, or bool
im.setField(fieldName, fieldValue); //set the value of the field using InstanceMirror
} else if (fieldValue is List) { // else if the fieldValue is a list
ClassMirror listCm = (cm.declarations[fieldName] as VariableMirror).type; //get the class mirror of the list
var listReflectee = listCm.newInstance(const Symbol(''), []).reflectee; //create an instance of the field
for(var element in fieldValue) { //for each element in the list
if(!isPrimitive(element)) { // if the element in the list is a map (i.e not num, string or bool)
var listType = listCm.typeArguments[0]; //get the TypeMirror of the list (i.e MyNestedClass from List<MyNestedClass>)
//This is the line that doesn't work correctly
//It should be something like:
//
// ClassMirror.fromSymbol(listType.simpleName).newInstance(const Symbol(''), []);
//
var listObject = (listType as ClassMirror).newInstance(const Symbol(''), []); //create an instance of the specified listType
mapToObject(element, listObject); //convert the element to Object
}
listReflectee.add(element); //add the element to the list
};
} else { //else (the field value is a map
ClassMirror fieldCm = (cm.declarations[fieldName] as VariableMirror).type; // get the field ClassMirror from the parent declarations
var reflectee = fieldCm.newInstance(const Symbol(''), []).reflectee; //create an instance of the field
mapToObject(fieldValue, reflectee); // convert the fieldValue, which is a map, to an object
im.setField(fieldName, reflectee); // set the value of the object previously converted to the corresponding field
}
});
}
As you can see the lines that are not actually working are:
var listType = listCm.typeArguments[0]; //get the TypeMirror of the list (i.e MyNestedClass from List<MyNestedClass>)
var listObject = (listType as ClassMirror).newInstance(const Symbol(''), []); //create an instance of the specified listType
since they are creating an instance on localClassMirror and not on MyNestedClass. I'm looking for a method similar to:
ClassMirror.fromSymbol(listType.simpleName).newInstance(const Symbol(''), []);
you can see the full source code in the next URL:
DSON Source Code
If you have the full qualified name of the class you should be able to find the type using libraryMirror and then it should be similar to your linked question to create an instance.
I haven't done this myself yet and have not code at hand.
see also: how to invoke class form dart library string or file
An alternative approach would be to create a map at application initialization time where you register the supported types with their name or an id and look up the type in this map (this is like it's done in Go)
Render attachment names from couchdb without conversion using handlebars or mustache template.
{
"_id":"123",
"_attachments":{
"evil.jpg":{
"content_type":"image/jpeg",
"revpos":32,
"digest":"md5-CKtT5WWRLkmGDD3/DhK6FQ==",
"length":41915,
"stub":true
}
}
}
I think this is duplicate of Getting key's in handlebar.
// based on the `#each` helper, requires jQuery (for jQuery.extend)
Handlebars.registerHelper('each_hash', function(context, options) {
var fn = options.fn, inverse = options.inverse;
var ret = "";
if(typeof context === "object") {
for(var key in context) {
if(context.hasOwnProperty(key)) {
// clone the context so it's not
// modified by the template-engine when
// setting "_key"
var ctx = jQuery.extend(
{"_key":key},
context[key]);
ret = ret + fn(ctx);
}
}
} else {
ret = inverse(this);
}
return ret;
});
The developers of handlebars are discussing putting this in
That helper should do the job anyway if you just want to add it. Your template would be like this.
{{#each_hash _attachments}}
{{_key}} - {{content_type}}
{{else}}
You didn't pass in an object!
{{/each_hash}}
The helper essentially just iterates through the object and does the conversion on the fly. It iterates through the object and adds the key as the _key variable. You don't have to include the else statement and it will return nothing by default.
For instance, I have a library and I would like to protect the source code to being viewed. The first method that comes to mind is to create public wrappers for private functions like the following
function executeMyCoolFunction(param1, param2, param3) {
return executeMyCoolFunction_(param1, param2, param3);
}
Only public part of the code will be visible in this way. It is fine, but all Google Service functions look like function abs() {/* */}. I am curious, is there an approach to hide library source code like Google does?
Edit 00: Do not "hide" a library code by using another library, i.e. the LibA with known project key uses the LibB with unknown project key. The public functions code of LibB is possible to get and even execute them. The code is
function exploreLib_(lib, libName) {
if (libName == null) {
for (var name in this) {
if (this[name] == lib) {
libName = name;
}
}
}
var res = [];
for (var entity in lib) {
var obj = lib[entity];
var code;
if (obj["toSource"] != null) {
code = obj.toSource();
}
else if (obj["toString"] != null) {
code = obj.toString();
}
else {
var nextLibCode = exploreLib_(obj, libName + "." + entity);
res = res.concat(nextLibCode);
}
if (code != null) {
res.push({ libraryName: libName, functionCode: code });
}
}
return res;
}
function explorerLibPublicFunctionsCode() {
var lstPublicFunctions = exploreLib_(LibA);
var password = LibA.LibB.getPassword();
}
I don't know what google does, but you could do something like this (not tested! just an idea):
function declarations:
var myApp = {
foo: function { /**/ },
bar: function { /**/ }
};
and then, in another place, an anonymous function writes foo() and bar():
(function(a) {
a['\u0066\u006F\u006F'] = function(){
// here code for foo
};
a['\u0062\u0061\u0072'] = function(){
// here code for bar
};
})(myApp);
You can pack or minify to obfuscate even more.
Edit: changed my answer to reflect the fact that an exception's stacktrace will contain the library project key.
In this example, MyLibraryB is a library included by MyLibraryA. Both are shared publicly to view (access controls) but only MyLibraryA's project key is made known. It appears it would be very difficult for an attacker to see the code in MyLibraryB:
//this function is in your MyLibraryA, and you share its project key
function executeMyCoolFunction(param1, param2, param3) {
for (var i = 0; i < 1000000; i++) {
debugger; //forces a breakpoint that the IDE cannot? step over
}
//... your code goes here
//don't share MyLibraryB project key
MyLibraryB.doSomething(args...);
}
but as per the #megabyte1024's comments, if you were to cause an exception in MyLibraryB.doSomething(), the stacktrace would contain the project key to MyLibraryB.