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How do I check whether a file exists without exceptions?
...open_it(), it's safer to use a try around the attempt to open it. Checking and then opening risks the file being deleted or moved or something between when you check and when you try to open it.
If you're not planning to open the file immediately, you can use os.path.isfile
Return True if path ...
“PKIX path building failed” and “unable to find valid certification path to requested target”
...got an error about certificate sun.security.validator.ValidatorException and sun.security.provider.certpath.SunCertPathBuilderException . Then I added twitter certificate by:
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Sorting a vector of custom objects
...ting a vector containing custom (i.e. user defined) objects.
Probably, standard STL algorithm sort along with a predicate (a function or a function object) which would operate on one of the fields (as a key for sorting) in the custom object should be used.
Am I on the right track?
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How many threads can a Java VM support?
... OS, on what other processes are doing, on what Java release you're using, and other factors. I've seen a Windows server have > 6500 Threads before bringing the machine down. Most of the threads were not doing anything, of course. Once the machine hit around 6500 Threads (in Java), the whole m...
How can I embed a YouTube video on GitHub wiki pages?
...o markup (though it's extremely easy to pickup). I am working on a package and am trying to get the wiki pages looking nice as a help manual. I can insert a YouTube video link into the wiki page pretty easily but how do I embed a YouTube video. I know this may not be possible.
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Accessing a Dictionary.Keys Key through a numeric index
...tem.Collections.ICollection' does not contain a definition for 'ElementAt' and no extension method 'ElementAt' accepting a first argument of type 'System.Collections.ICollection' could be found
– v.oddou
Feb 20 '15 at 6:59
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Writing a compiler in its own language
...nguage Foo. You use the first bootstrap compiler to compile the compiler, and then use this compiled compiler to compile everything else (including future versions of itself).
Most languages are indeed created in this fashion, partially because language designers like to use the language they are ...
In Python, how do I split a string and keep the separators?
... It's seriously underdocumented. I've been using Python for 14 years and only just found this out.
– smci
Jun 19 '13 at 16:33
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Java Reflection Performance
...operations have slower performance than their non-reflective counterparts, and should be avoided in sections of code which are called frequently in performance-sensitive applications.
Here's a simple test I hacked up in 5 minutes on my machine, running Sun JRE 6u10:
public class Main {
publ...
Elastic search, multiple indexes vs one index and types for different data sets?
I have an application developed using the MVC pattern and I would like to index now multiple models of it, this means each model has a different data structure.
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