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Reference: What is variable scope, which variables are accessible from where and what are “undefined
...included code as applies to any other code: only functions separate scope. For the purpose of scope, you may think of including files like copy and pasting code:
c.php
<?php
function myFunc() {
include 'a.php';
echo $foo; // works
}
myFunc();
echo $foo; // doesn't work!
In the a...
How to dynamically create a class?
...
Yes, you can use System.Reflection.Emit namespace for this. It is not straight forward if you have no experience with it, but it is certainly possible.
Edit: This code might be flawed, but it will give you the general idea and hopefully off to a good start towards the goal....
How to create local notifications?
...
Here is sample code for LocalNotification that worked for my project.
Objective-C:
This code block in AppDelegate file :
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
...
Is the C# static constructor thread safe?
... constructors are guaranteed to be run only once per application domain, before any instances of a class are created or any static members are accessed. https://docs.microsoft.com/en-us/dotnet/csharp/programming-guide/classes-and-structs/static-constructors
The implementation shown is thread safe f...
Can you find all classes in a package using reflection?
...the VM which classes it can provide, instead they are just handed requests for classes, and have to return a class or throw an exception.
However, if you write your own class loaders, or examine the classpaths and it's jars, it's possible to find this information. This will be via filesystem operat...
How to output a multiline string in Bash?
...
Here documents are often used for this purpose.
cat << EOF
usage: up [--level <n>| -n <levels>][--help][--version]
Report bugs to:
up home page:
EOF
They are supported in all Bourne-derived shells including all versions of Bash.
...
Swift Programming: getter/setter in stored property
...is this:
var rank: Int = 0 {
didSet {
// Say 1000 is not good for you and 999 is the maximum you want to be stored there
if rank >= 1000 {
rank = 999
}
}
}
share
|
...
Pandas percentage of total with groupby
... 'sales': [np.random.randint(100000, 999999)
for _ in range(12)]})
state_office = df.groupby(['state', 'office_id']).agg({'sales': 'sum'})
# Change: groupby state_office and divide by sum
state_pcts = state_office.groupby(level=0).apply(lambda x:
...
How to throw std::exceptions with variable messages?
This is an example of what I often do when I want to add some information to an exception:
8 Answers
...
Why do I get a segmentation fault when writing to a “char *s” initialized with a string literal, but
...shes if I try to assign a new value to p[i].
A: A string literal (the formal term
for a double-quoted string in C
source) can be used in two slightly
different ways:
As the initializer for an array of char, as in the declaration of char a[] , it specifies the initial values
of t...