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How to avoid isset() and empty()
I have several older applications that throw a lot of "xyz is undefined" and "undefined offset" messages when running on the E_NOTICE error level, because the existence of variables is not explicitly checked using isset() and consorts.
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What is the difference between 'E', 'T', and '?' for Java generics?
I come across Java code like this:
6 Answers
6
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Find unused code [closed]
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Yes, ReSharper does this. Right click on your solution and selection "Find Code Issues". One of the results is "Unused Symbols". This will show you classes, methods, etc., that aren't used.
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When should I use the Visitor Design Pattern? [closed]
I keep seeing references to the visitor pattern in blogs but I've got to admit, I just don't get it. I read the wikipedia article for the pattern and I understand its mechanics but I'm still confused as to when I'd use it.
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Checking network connection
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Perhaps you could use something like this:
import urllib2
def internet_on():
try:
urllib2.urlopen('http://216.58.192.142', timeout=1)
return True
except urllib2.URLError as err:
return False
Currently, 216.58.192.142 is one of ...
JavaScript: How to find out if the user browser is Chrome?
I need some function returning a boolean value to check if the browser is Chrome .
13 Answers
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Does HTTP use UDP?
This might be a silly question:
14 Answers
14
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Vim clear last search highlighting
...r doing a search in Vim, I get all the occurrences highlighted. How can I disable that? I now do another search for something gibberish that can't be found.
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Get decimal portion of a number with JavaScript
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answered Dec 22 '10 at 18:21
Ignacio Vazquez-AbramsIg...
Postgres unique constraint vs index
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I had some doubts about this basic but important issue, so I decided to learn by example.
Let's create test table master with two columns, con_id with unique constraint and ind_id indexed by unique index.
create table master (
con_id integer uni...