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Dim Value As LongLong A LongLong is a signed 64 bit data type and is only available in 64 bit applications. It is not available in 32 bit applications running on 64 bit operating systems. It can store integer values in the range of -9,223,372,036,854,775,808 to 9,223,372,036,854,775,807 and attem...

Dim Value As LongPtr The LongPtr was introduced into VBA in order to support 64 bit platforms. On a 32 bit system, it is treated as a Long and on 64 bit systems it is treated as a LongLong. It's primary use is in providing a portable way to store and pass pointers on both architectures (See Chan...

Callbacks can be used to provide code to be executed after a method has completed: /** * @arg {Function} then continuation callback */ function doSomething(then) { console.log('Doing something'); then(); } // Do something, then execute callback to log 'done' doSomething(function () ...

Callbacks are often used to provide error handling. This is a form of control flow branching, where some instructions are executed only when an error occurs: const expected = true; function compare(actual, success, failure) { if (actual === expected) { success(); } else { failure...

#Get the active Worksheet my $Book = $Excel->Activewindow; my $Sheet = $Book->Activesheet; #List of Worksheet names my @list_Sheet = map { $_->{'Name'} } (in $Book->{Worksheets}); #Access a given Worksheet my $Sheet = $Book->Worksheets($list_Sheet[0]); #Add new Worksheet...

#Edit the value of a cell (2 methods) $Sheet->Range("A1")->{Value} = 1234; $Sheet->Cells(1,1)->{Value} = 1234; #Edit the values in a range of cells $Sheet->Range("A8:C9")->{Value} = [[ undef, 'Xyzzy', 'Plugh' ], [ 42, 'Pe...

#Insert a row before/after line 22 $Sheet->Rows("22:22")->Insert(xlUp, xlFormatFromRightOrBelow); $Sheet->Rows("23:23")->Insert(-4121,0); #xlDown is -4121 and that xlFormatFromLeftOrAbove is 0 #Delete a row $Sheet->Rows("22:22")->Delete(); ...

Setting a field to NULL works exactly like with any other value: UPDATE Employees SET ManagerId = NULL WHERE Id = 4

Use appearanceWhenContainedInInstancesOfClasses: to customize the appearance for instance of a class when contained within an instance of container class. For example customization of UILabel's textColor and backgroundColor within ViewController class will look like this: Set UILabel text color Sw...

The response to a CORS request must include an Access-Control-Allow-Origin header, which dictates what origins are allowed to use the CORS resource. This header can take one of three values: An origin. Doing this permits requests from that origin only. The character *. This permits requests from...

Allowing user credentials or the user's session to be sent with a CORS request allows the server to persist user data across CORS requests. This is useful if the server needs to check if the user is logged in before providing data (for example, only performing an action if a user is logged in - this...

When a server receives a preflight request, it must check if it supports the requested method and headers, and send back a response that indicates its ability to support the request, as well as any other permitted data (such as credentials). These are indicated in access-control Allow headers. The ...

var app = {}; app.signUp = function(){ app.userName = $('#userName').val(); app.password = $('#password').val(); app.email = $('#form-email').val(); app.phoneNumber = $('#form-phone').val(); app.emailRegex = ...

Sometimes you want to convert your enum to a String, there are two ways to do that. Assume we have: public enum Fruit { APPLE, ORANGE, STRAWBERRY, BANANA, LEMON, GRAPE_FRUIT; } So how do we convert something like Fruit.APPLE to "APPLE"? Convert using name() name() is an inte...

When we want to count the number of items in an iterable, that meet some condition, we can use comprehension to produce an idiomatic syntax: # Count the numbers in `range(1000)` that are even and contain the digit `9`: print (sum( 1 for x in range(1000) if x % 2 == 0 and '9' in str...

Functionality in metaclasses can be changed so that whenever a class is built, a string is printed to standard output, or an exception is thrown. This metaclass will print the name of the class being built. class VerboseMetaclass(type): def __new__(cls, class_name, class_parents, class_dict)...

In Java, we can convert between integer values and floating-point values. Also, since every character corresponds to a number in the Unicode encoding, char types can be converted to and from the integer and floating-point types. boolean is the only primitive datatype that cannot be converted to or f...

Recursion can be used to receive multiple messages defmodule Processes do def receiver do receive do {:ok, val} -> IO.puts "Received Value: #{val}" _ -> IO.puts "Received something else" end...

Detailed instructions on getting jvm set up or installed.

Like the built-in python interactive shell, IPython is a REPL (Read-Evaluate-Print Loop) shell, with a variety of features that make it more pleasant to use for day-to-day Python development than the built-in REPL shell. Installation To install it: pip install ipython Or, via Anaconda: # To i...