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How do you check in python whether a string contains only numbers?
....isdigit():
From the isdigit documentation:
str.isdigit()
Return True if all characters in the string are digits and there is at least one character, False otherwise. Digits include decimal characters and digits that need special handling, such as the compatibility superscript digits. This covers ...
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...
Computed / calculated / virtual / derived columns in PostgreSQL
...(Not in Postgres 13, yet) .
Related:
Attribute notation for function call gives error
Until then, you can emulate VIRTUAL generated columns with a function using attribute notation (tbl.col) that looks and works much like a virtual generated column. That's a bit of a syntax oddity which exi...
ImportError: no module named win32api
...m using Python 2.7 and I want to use pywin32-214 on Windows 7 . I installed pywin32-214 by using the msi installer. But when I import win32api in my Python script, it throws the error:
...
Why do you use typedef when declaring an enum in C++?
...
In C, declaring your enum the first way allows you to use it like so:
TokenType my_type;
If you use the second style, you'll be forced to declare your variable like this:
enum TokenType my_type;
As mentioned by others, this doesn't make a difference in C++. M...
Is it possible to rotate a drawable in the xml description?
..."
android:pivotY="50%"
android:drawable="@drawable/mainmenu_background">
</rotate>
The fromDegrees is important.
Basically this is a rotate animation defined in XML. With fromDegrees you define the initial rotated state. The toDegrees is the final rotated state of the dra...
Does anyone have benchmarks (code & results) comparing performance of Android apps written in Xamari
...y to stay inside the Mono VM most of the time, we do not know how Mono actually accesses the disk.
It is also telling that our C# code uses SQLite.NET (https://github.com/praeclarum/sqlite-net). Identical fetches using the SQLite.NET code are also 2x slower than using Android's Java SQLite wrapper....
Check if URL has certain string with PHP
...URL and the rest check if it contains the word "car".
$url = 'http://' . $_SERVER['SERVER_NAME'] . $_SERVER['REQUEST_URI'];
if (strpos($url,'car') !== false) {
echo 'Car exists.';
} else {
echo 'No cars.';
}
shar...
How to set the thumbnail image on HTML5 video?
...reload="metadata">
<source src="https://www.w3schools.com/html/mov_bbb.mp4#t=0.5" type="video/mp4">
</video>
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TypeScript function overloading
...use, when both functions are compiled to JavaScript, their signature is totally identical. As JavaScript doesn't have types, we end up creating two functions taking same number of arguments. So, TypeScript restricts us from creating such functions.
TypeScript supports overloading based on number of...