anonymous-function

for (var i = 0; i < somearray.length; i++) { myclass.foo({'arg1':somearray[i][0]}, function() { console.log(somearray[i][0]); }); } How do I pass somearray or one of its indexes into the anonymous function ? somearray is already in the global scope, but I still get somearray[i] is undefined The i in the anonymous function captures the variable i , not its value . By the end of the loop, i is equal to somearray.length , so when you invoke the function it tries to access an non-existing element array. You can fix this by making a function-constructing function that captures the variable's value:

WordPress hooks can be used in two ways: using callback function name and appropriate function add_action( 'action_name', 'callback_function_name' ); function callback_function_name() { // do something } using anonymous function (closure) add_action( 'action_name', function() { // do something } ); Is there any difference for WordPress what way to use? What is prefered way and why? TeeDeJee The disadvantage of the anonymous function is that you're not able to remove the action with remove_action . Important: To remove a hook, the $function_to_remove and $priority arguments must match when the

In this SO thread, Brian Postow suggested a solution involving fake anonymous functions: make a comp(L) function that returns the version of comp for arrays of length L... that way L becomes a parameter, not a global How do I implement such a function? Adam Rosenfield See the answer I just posted to that question. You can use the callback(3) library to generate new functions at runtime. It's not standards compliant, since it involves lots of ugly platform-specific hacks, but it does work on a large number of systems. The library takes care of allocating memory, making sure that memory is

Just ran into this today An anonymous function or method group cannot be used as a constituent value of a dynamically bound operation. when trying to do static R ifNotNull<R>(dynamic o, Func<dynamic, R> returnFunc, R otherwise) { return ReferenceEquals(null, o) ? otherwise : returnFunc(o); } and use it with dynamic firstAddress = ...; return ifNotNull<string>(firstAddress, (a) => a.address_1, null) Now most of the limitations on dynamics make sense to me - you can't use an extension method because how is the compiler supposed to decide which static to compile it to? But I don't get this here.

I need to be able to do this: var getHed = () => { // do stuff return new { Property1 = value, Property2 = value2, etc...}; }; var anonymousClass = getHed(); But I get an error which indicates I need to explicitly declare getHed. How do I declare Func such that T is the anonymous type I am returning? In case you are curious why I need to do this, it is because I am using 3rd party software that allows customization code, but only within a single method. This can become very difficult to manage. I had the idea that I could use anonymous methods to help keep the procedural code organized. In

I'm trying to define an anonymous function to do a dot product, I can code this as a private function without any problem but I am struggling with the anonymous function syntax. I know I could implement this differently but I am trying to understand how to define anonymous functions with pattern matching and recursion. This is my current implementation dot = fn [i|input],[w|weights], acc -> dot.(input,weights,i*w+acc) [],[bias],acc -> acc + bias end And I get this error on compile: function dot/0 undefined Any hints? Is this just not possible? It is not possible to recur on anonymous functions

I want to assign a function implementation dynamically. Let's start with the following: class Doer(object): def __init__(self): self.name = "Bob" def doSomething(self): print "%s got it done" % self.name def doItBetter(self): print "Done better" In other languages we would make doItBetter an anonymous function and assign it to the object. But no support for anonymous functions in Python. Instead, we'll try making a callable class instance, and assign that to the class: class Doer(object): def __init__(self): self.name = "Bob" class DoItBetter(object): def __call__(self): print "%s got it done

Is there a difference between expression lambda and statement lambda? If so, what is the difference? Found this question in the below link but could not understand the answer What is Expression Lambda? C# interview Questions The answer mentioned in that link is this A lambda expression with an expression on the right side is called an expression lambda. Per my understanding always the expression is in the right hand side only. That is why I am asking this question. Is there anything I am unaware of? This is indeed confusing jargon; we couldn't come up with anything better. A lambda expression