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Difference between Select and ConvertAll in C#
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Select is a LINQ extension method and works on all IEnumerable<T> objects whereas ConvertAll is implemented only by List<T>. The ConvertAll method exists since .NET 2.0 whereas LINQ was introduced with 3.5.
You should favor Select over ConvertAll...
mongodb: insert if not exists
...-find-else-update block entirely. It will insert if the key doesn't exist and will update if it does.
Before:
{"key":"value", "key2":"Ohai."}
After:
{"key":"value", "key2":"value2", "key3":"value3"}
You can also specify what data you want to write:
data = {"$set":{"key2":"value2"}}
Now yo...
iOS5 Storyboard error: Storyboards are unavailable on iOS 4.3 and prior
I've built a small app using storyboards and it ran great. Just before final testing I decided to try it out to see if it runs on iOS 4.3. I clicked on the gray 5.0 in the project settings and selected 4.3.
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Java packages com and org
What are the meaning of the packages org and com in Java?
4 Answers
4
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How do I convert a String object into a Hash object?
...en its string representation is "{:a=>#<Object:0x7f66b65cf4d0>}", and I can't use eval to turn it back into a hash because #<Object:0x7f66b65cf4d0> isn't valid Ruby syntax.
However, if all that's in the hash is strings, symbols, numbers, and arrays, it should work, because those have...
Big O of JavaScript arrays
Arrays in JavaScript are very easy to modify by adding and removing items. It somewhat masks the fact that most languages arrays are fixed-size, and require complex operations to resize. It seems that JavaScript makes it easy to write poorly performing array code. This leads to the question:
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Wget output document and headers to STDOUT
I'm trying to output document body and its headers to stdout with wget by wget -S -O - http://google.com
5 Answers
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Read input from console in Ruby?
...ing like that?
Update
Kernel.gets tries to read the params found in ARGV and only asks to console if not ARGV found. To force to read from console even if ARGV is not empty use STDIN.gets
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I want to get Year, Month, Day, etc from Java Date to compare with Gregorian Calendar date in Java.
....add(Calendar.DAY_OF_MONTH, -48) to do day arithmetic on Calendar objects. And you can compare two Calendar objects using cal.compareTo(anotherCal).
– Florent Guillaume
Feb 27 '12 at 23:55
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Use find command but exclude files in two directories
...t to find files that end with _peaks.bed , but exclude files in the tmp and scripts folders.
6 Answers
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