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What are the effects of exceptions on performance in Java?

... the exceptions themselves, the exact actions taken in exception handlers, etc. The upshot is that when an exception isn't thrown, you don't pay a cost, so when the exceptional condition is sufficiently rare exception handling is faster than using an if every time. The full post is very much worth...
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Referring to the null object in Python

...nd is used to control and test special conditions (e.g. boundaries, state, etc.). Such a value is called a sentinel and it can be used the way None is used as a signal. It's trivial to create a sentinel in Python. undefined = object() The undefined object above is unique and doesn't do much of anyt...
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What is the purpose of setting a key in data.table?

...along with associated information (city, state, population, median income, etc.). If I want to look up the information for a specific zip code, the search (filter) is about 1000 times faster if I setkey(ZIP,zipcode) first. Another benefit has to do with joins. Suppose a have a list of people and th...
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What's the difference between “groups” and “captures” in .NET regular expressions?

...avior causes group's specification, like (...)(...), (...){2} or (.{3}){2} etc. Hopefully it will help shed some light on the differences between Captures, Groups and Matches as well. share | imp...
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Understanding the Use of ColorMatrix and ColorMatrixColorFilter to Modify a Drawable's Hue

...Note that a lot more can be done with color matrices. Including inverting, etc... public class ColorFilterGenerator { /** * Creates a HUE ajustment ColorFilter * @see http://groups.google.com/group/android-developers/browse_thread/thread/9e215c83c3819953 * @see http://gskinner.com/blog/archi...
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Tactics for using PHP in a high-load site

...l of the file concatenations, minification, file renaming to include hash, etc for all static content. It'll should only add a little processing overhead to the servers initially until the caches (and CDN(s)) are populated with most of the content. Also, for security, it's generally a bad idea to pu...
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is there a css hack for safari only NOT chrome?

... by posting a comment about it, Post Your Browser and Device (MacBook/IPad/etc... with both browser and OS version numbers!) Claiming none of these work is not accurate (and actually not even possible.) Many of these are not really 'hacks' but code built into versions of Safari by Apple. More info i...
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What does the Java assert keyword do, and when should it be used?

... try to trap, log, or retry/recover from OutOfMemoryError, AssertionError, etc. – Aleksandr Dubinsky Jun 16 '16 at 21:39 1 ...
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How to strip HTML tags from a string in SQL Server?

...tween the tags. Ideally also replacing things like < with < , etc. 11 Answers ...
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How to handle Handler messages when activity/fragment is paused

...savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); if (savedInstanceState == null) { final Fragment state = new State(); final FragmentManager fm = getFragmentManager(); final FragmentTransaction ft = ...