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When should we use mutex and when should we use semaphore
When should we use mutex and when should we use semaphore ?
12 Answers
12
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In Python how should I test if a variable is None, True or False
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Don't fear the Exception! Having your program just log and continue is as easy as:
try:
result = simulate(open("myfile"))
except SimulationException as sim_exc:
print "error parsing stream", sim_exc
else:
if result:
print "result pass"
else:
print...
What is the difference between “instantiated” and “initialized”?
...in C# are in 1 of 2 groups. Value types or Reference types. Types like int and DateTime are value types. In contrast, any class you create is a reference type. C# strings are also a reference type. Most things in the .NET framework are reference types.
Parts of a Variable
There is the variable nam...
Generic method multiple (OR) type constraint
...t types. That means you could just as well leave out the generic parameter and provide overloads.
– Botz3000
May 31 '12 at 13:00
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Ignoring time zones altogether in Rails and PostgreSQL
I'm dealing with dates and times in Rails and Postgres and running into this issue:
2 Answers
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What is better, adjacency lists or adjacency matrices for graph problems in C++?
...ts or adjacency matrix, for graph problems in C++?
What are the advantages and disadvantages of each?
11 Answers
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How to verify an XPath expression in Chrome Developers tool or Firefox's Firebug?
...here for more details):
Search in Elements panel like below
Execute $x() and $$() in Console panel, as shown in Lawrence's answer
Third party extensions (not really necessary in most of the cases, could be an overkill)
Here is how you search XPath in Elements panel:
Press F12 to open Chrome De...
SQL: IF clause within WHERE clause
...ion in most cases. In my case, I wanted the change the comparison operator and hence I used the next approach.
– Birla
Nov 15 '14 at 11:59
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Best Practice: Software Versioning [closed]
Is there any guideline or standard best practice how to version a software you develop in your spare time for fun, but nevertheless will be used by some people? I think it's necessary to version such software so that you know about with version one is talking about (e.g. for bug fixing, support, and...
What's the difference between equal?, eql?, ===, and ==?
I am trying to understand the difference between these four methods. I know by default that == calls the method equal? which returns true when both operands refer to exactly the same object.
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