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Default value in Go's method
...s on the subject, but here are some specific examples.
**Option 1:** The caller chooses to use default values
// Both parameters are optional, use empty string for default value
func Concat1(a string, b int) string {
if a == "" {
a = "default-a"
}
if b == 0 {
b = 5
}
return fmt.S...
void in C# generics?
...nctions need to return null, but if it unifies your code, it should be a small price to pay.
This inability to use void as a return type is at least partially responsible for a split between the Func<...> and Action<...> families of generic delegates: had it been possible to return void...
Does C have a “foreach” loop construct?
Almost all languages have a foreach loop or something similar. Does C have one? Can you post some example code?
12 Answer...
C# Lazy Loaded Automatic Properties
... 4.0 Lazy<T> type to create this pattern
private Lazy<string> _someVariable =new Lazy<string>(SomeClass.IOnlyWantToCallYouOnce);
public string SomeVariable => _someVariable.Value;
This code will lazily calculate the value of _someVariable the first time the Value expression i...
What is the Swift equivalent to Objective-C's “@synchronized”?
...ty that you have with @synchronized.
– Michael Waterfall
Oct 23 '14 at 16:46
9
With this approach...
How do you use the “WITH” clause in MySQL?
I am converting all my SQL Server queries to MySQL and my queries that have WITH in them are all failing. Here's an example:
...
Python read-only property
...
Generally, Python programs should be written with the assumption that all users are consenting adults, and thus are responsible for using things correctly themselves. However, in the rare instance where it just does not make sens...
How do I use Django templates without the rest of Django?
...without having a settings.py file (and others) and having to set the DJANGO_SETTINGS_MODULE environment variable?
13 Answer...
Using comparison operators in Scala's pattern matching system
...t; println("less than ten")
}
Edit: Note that this is more than superficially different to putting an if after the =>, because a pattern won't match if the guard is not true.
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What are valid values for the id attribute in HTML?
...
For HTML 4, the answer is technically:
ID and NAME tokens must begin with a letter ([A-Za-z]) and may be followed by any number of letters, digits ([0-9]), hyphens ("-"), underscores ("_"), colons (":"), and periods (".").
HTML 5 is even more permissiv...