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Why is there no logical xor in JavaScript?
...r. Mainly because it's not useful. Bitwise XOR is extremely useful, but in all my years of programming I have never needed a logical XOR.
If you have two boolean variables you can mimic XOR with:
if (a != b)
With two arbitrary variables you could use ! to coerce them to boolean values and then u...
django - why is the request.POST object immutable?
...
It's a bit of a mystery, isn't it? Several superficially plausible theories turn out to be wrong on investigation:
So that the POST object doesn't have to implement mutation methods? No: the POST object belongs to the django.http.QueryDict class, which implements a full set ...
change type of input field with jQuery
... or part of their security model, but jQuery isn't specific):
// We can't allow the type property to be changed (since it causes problems in IE)
if ( name == "type" && jQuery.nodeName( elem, "input" ) && elem.parentNode )
throw "type property can't be changed";
...
How do you pass arguments to define_method?
... your defined method accepts arguments. When you define a method you're really just nicknaming the block and keeping a reference to it in the class. The parameters come with the block. So:
define_method(:say_hi) { |other| puts "Hi, " + other }
...
hadoop No FileSystem for scheme: file
...tem, hadoop-hdfs for DistributedFileSystem) each contain a different file called org.apache.hadoop.fs.FileSystem in their META-INFO/services directory. This file lists the canonical classnames of the filesystem implementations they want to declare (This is called a Service Provider Interface impleme...
Bootstrap 3 Glyphicons are not working
...ome kind of "E003" error. Any ideas why this is happening? I tried both locally and online and I still get the same problem.
...
Cross-Domain Cookies
...erver side you need to have the following headers:
header("Access-Control-Allow-Origin: http://origin.domain:port");
header("Access-Control-Allow-Credentials: true");
header("Access-Control-Allow-Methods: GET, POST");
header("Access-Control-Allow-Headers: Content-Type, *");
Within the PHP-file yo...
How to find if a native DLL file is compiled as x64 or x86?
...
You can use DUMPBIN too. Use the /headers or /all flag and its the first file header listed.
dumpbin /headers cv210.dll
64-bit
Microsoft (R) COFF/PE Dumper Version 10.00.30319.01
Copyright (C) Microsoft Corporation. All rights reserved.
Dump of file cv210.dll
PE ...
How do I remove a MySQL database?
...e users; i.e., force MySQL to read the user's privileges again.
-- DELETE ALL RECIPE
drop schema <database_name>;
-- Same as `drop database <database_name>`
drop user <a_user_name>;
-- You may need to add a hostname e.g `drop user bob@localhost`
FLUSH PRIVILEGES;
Good luck!
...
Is it worthwile to learn assembly language? [closed]
...end it as a good introduction to the language itself -- although for the really interesting stuff you have to hunt out obsessives on the net.
I think it's useful to understand what happens at the lower levels. As you research assembler you will learn about cpu pipelining, branch prediction, cache a...