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Performance surprise with “as” and nullable types
...'m just revising chapter 4 of C# in Depth which deals with nullable types, and I'm adding a section about using the "as" operator, which allows you to write:
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What is the benefit of using Fragments in Android, rather than Views?
When developing for Android , you can set your target (or minimum) sdk to 4 (API 1.6) and add the android compatibility package (v4) to add support for Fragments . Yesterday I did this and successfully implemented Fragments to visualize data from a custom class.
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How can I read command line parameters from an R script?
I've got a R script for which I'd like to be able to supply several command-line parameters (rather than hardcode parameter values in the code itself). The script runs on Windows.
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boost::flat_map and its performance compared to map and unordered_map
...haven't been able to find any performance comparisons. How does it compare and what are the best use cases for it?
2 Answer...
How to get users to read error messages?
...ind yourself at a high risk that users will not read your carefully worded and enlightening error messages, but just click on the first button available with a shrug of frustration.
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Should I use pt or px?
What is the difference between pt and px in CSS? Which one should I use and why?
5 Answers
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How to set HTTP headers (for cache-control)?
...ive CACHE-CONTROL:NO-CACHE indicates cached information should not be used
and instead requests should be forwarded to the origin server. This directive has the same semantics as the PRAGMA:NO-CACHE.
Clients SHOULD include both PRAGMA: NO-CACHE and CACHE-CONTROL: NO-CACHE when a no-cache request is...
Upgrade python in a virtualenv
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Did you see this? If I haven't misunderstand that answer, you may try to create a new virtualenv on top of the old one. You just need to know which python is going to use your virtualenv (you will need to see your virtualenv version).
If your virtualenv is install...
How do I convert a column of text URLs into active hyperlinks in Excel?
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If you don't want to make a macro and as long as you don't mind an additional column, then just create a new column alongside your column of URLs.
In the new column type in the formula =HYPERLINK(A1) (replacing A1 with whatever cell you are interested in). T...
How do DATETIME values work in SQLite?
I’m creating Android apps and need to save date/time of the creation record. The SQLite docs say, however, "SQLite does not have a storage class set aside for storing dates and/or times" and it's "capable of storing dates and times as TEXT, REAL, or INTEGER values".
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