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How to check if array element exists or not in javascript?
...hey have the prototype method hasOwnProperty "inherited" from Object
in my testing, hasOwnProperty can check if anything exists at an array index.
So, as long as the above is true, you can simply:
const arrayHasIndex = (array, index) => Array.isArray(array) && array.hasOwnProperty(inde...
Clearing a string buffer/builder after loop
... the string mutability, not from saving the instantiation. here's a quick test of 1e8 iterations: inside loop (2.97s): ideone.com/uyyTL14w, outside loop (2.87s): ideone.com/F9lgsIxh
– Mark Elliot
Feb 11 '10 at 5:46
...
Coding Practices which enable the compiler/optimizer to make a faster program
...ithout branching:
bool status = true;
status = status && /* first test */;
status = status && /* second test */;
The short circuiting of the Logical AND operator (&&) prevents execution of the tests if the status is false.
Example:
struct Reader_Interface
{
virtual boo...
Hidden Features of ASP.NET [closed]
...
While testing, you can have emails sent to a folder on your computer instead of an SMTP server. Put this in your web.config:
<system.net>
<mailSettings>
<smtp deliveryMethod="SpecifiedPickupDirectory">...
Timeout expired. The timeout period elapsed prior to completion of the operation or the server is no
...al query plan. It can be resolved by clearing the statistics:
exec sp_updatestats
If that doesn't work you could also try
dbcc freeproccache
You should not do this when your server is under heavy load because it will temporarily incur a big performace hit as all stored procs and queries are re...
Getting the folder name from a path
...directory for a path when no filename is in the path:
for example "c:\tmp\test\visual";
string dir = @"c:\tmp\test\visual";
Console.WriteLine(dir.Replace(Path.GetDirectoryName(dir) + Path.DirectorySeparatorChar, ""));
Output:
visual
...
When should null values of Boolean be used?
... started to convert my boolean s to Boolean s. This can cause crashes in tests such as
14 Answers
...
How to write a switch statement in Ruby
...when clauses as seen above. Ranges, classes and all sorts of things can be tested for rather than just equality.
Unlike switch statements in many other languages, Ruby’s case does not have fall-through, so there is no need to end each when with a break. You can also specify multiple matches in a ...
NodeJS require a global module/package
... What if I don't have a project? Say ~/some-stand-alone-random-nodejs-test.js. I don't want to turn my home folder into a project directory. I don't want to create new folders for every small experiment.
– AnnanFay
Jul 10 '14 at 20:40
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How to link C++ program with Boost using CMake
...2 xy xy 4.0K May 28 19:23 ./
-rw-rw-r-- 1 xy xy 2.3M May 28 19:23 libboost_test_exec_monitor.a
-rw-rw-r-- 1 xy xy 2.2M May 28 19:23 libboost_unit_test_framework.a
.......
xy@xy:~/boost_install/lib$ ll -th include/
total 20K
drwxrwxr-x 110 xy xy 12K May 28 19:22 boost/
If you are interested in ho...