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Best approach for designing F# libraries for use from both F# and C#
... function that you wrote, so I'll add some higher-level comments. First of all, you should read the F# Component Design Guidelines (referenced already by gradbot). This is a document that explains how to design F# and .NET libraries using F# and it should answer many of your questions.
When using F...
Refused to display in a frame because it set 'X-Frame-Options' to 'SAMEORIGIN'
...ight='760' src="https://www.youtube.com/embed/dQw4w9WgXcQ" frameborder="0" allowfullscreen></iframe>
– backwardm
Aug 5 '15 at 20:28
2
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What's a good way to extend Error in JavaScript?
...nvironments set the stack property, but fileName and lineNumber are practically useless to be used in inheritance.
So, the minimalistic approach is:
function MyError(message) {
this.name = 'MyError';
this.message = message;
this.stack = (new Error()).stack;
}
MyError.prototype = new Er...
Is there a difference between “==” and “is”?
... a
True
In your case, the second test only works because Python caches small integer objects, which is an implementation detail. For larger integers, this does not work:
>>> 1000 is 10**3
False
>>> 1000 == 10**3
True
The same holds true for string literals:
>>> "a" i...
How can i tell if an object has a key value observer attached
...
Put a try catch around your removeObserver call
@try{
[someObject removeObserver:someObserver forKeyPath:somePath];
}@catch(id anException){
//do nothing, obviously it wasn't attached because an exception was thrown
}
...
How can I force users to access my page over HTTPS instead of HTTP?
...
The way I've done it before is basically like what you wrote, but doesn't have any hardcoded values:
if($_SERVER["HTTPS"] != "on")
{
header("Location: https://" . $_SERVER["HTTP_HOST"] . $_SERVER["REQUEST_URI"]);
exit();
}
...
PHP: How to send HTTP response code?
...-Code: 404', true, 404);
I recommend the 2nd one. The first does work on all browsers I have tested, but some minor browsers or web crawlers may have a problem with a header line that only contains a colon. The header field name in the 2nd. variant is of course not standardized in any way and coul...
Pandas count(distinct) equivalent
...ing pandas as a db substitute as I have multiple databases (oracle, mssql, etc) and I am unable to make a sequence of commands to a SQL equivalent.
...
List comprehension vs map
...ing map() over list comprehension or vice versa? Is either of them generally more efficient or considered generally more pythonic than the other?
...
Check if table exists and if it doesn't exist, create it in SQL Server 2008
...read, and you don't have to worry about sys.objects vs. sysobjects vs. sys.all_objects
vs. sys.tables. Basic form:
IF object_id('MyTable') is not null
PRINT 'Present!'
ELSE
PRINT 'Not accounted for'
Of course this will show as "Present" if there is any object present with that name. If yo...