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Check if character is number?
...ou can use regexp like this:
function is_numeric(str){
return /^\d+$/.test(str);
}
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Finding the source code for built-in Python functions?
...y
Modules/_<module>.c (if there’s also a C accelerator module)
Lib/test/test_<module>.py
Doc/library/<module>.rst
For extension-only modules, the typical layout is:
Modules/<module>module.c
Lib/test/test_<module>.py
Doc/library/<module>.rst
For buil...
What does the Java assert keyword do, and when should it be used?
...
@ElMac - assertions are for the dev/debug/test parts of the cycle - they are not for production. An if block runs in prod. Simple assertions won't break the bank, but expensive assertions that do complex data validation might bring down your production environment,...
IE7 Z-Index Layering Issues
I've isolated a little test case of IE7's z-index bug, but don't know how to fix it.
I have been playing with z-index all day long.
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NSUserDefaults removeObjectForKey vs. setObject:nil
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Swift 3.0
The below answer is no longer the case when I tested this.
When set to nil the result is NSCFData being stored. Possibly an NSNull object reference, but I am not positive.
To completely remove a value for a key use UserDefaults.standard.removeObject(forKey: "YourDefaul...
How should I use git diff for long lines?
... line.
For example, instead of getting something like this:
diff --git a/test-file.txt b/test-file.txt
index 19e6adf..eb6bb81 100644
--- a/test-file.txt
+++ b/test-file.txt
@@ -1 +1 @@
-this is a short line
+this is a slightly longer line
You might get something like this:
diff --git a/test-fil...
Does Parallel.ForEach limit the number of active threads?
...a few hours I watched the Parallel library spin off over 8,000 threads. I tested using MaxDegreeOfParallelism and sure enough the 8000+ threads disappeared. I have tested it multiple times now with the same result.
– Jake Drew
Jun 24 '16 at 6:40
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List of Big-O for PHP functions
...ose who doubt that PHP array lookups are O(N), I've written a benchmark to test that (they are still effectively O(1) for most realistic values).
$tests = 1000000;
$max = 5000001;
for( $i = 1; $i <= $max; $i += 10000 ) {
//create lookup array
$array = array_fill( 0, $i, NULL );
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Why does my JavaScript code receive a “No 'Access-Control-Allow-Origin' header is present on the req
I am trying to do authorization using JavaScript by connecting to the RESTful API built-in Flask . However, when I make the request, I get the following error:
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How to test if a dictionary contains a specific key? [duplicate]
What's the cleanest way to test if a dictionary contains a key?
1 Answer
1
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