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How to convert lazy sequence to non-lazy in Clojure
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doall is all you need. Just because the seq has type LazySeq doesn't mean it has pending evaluation. Lazy seqs cache their results, so all you need to do is walk the lazy seq once (as doall does) in order to force it all, and t...
Why does Ruby 1.9.2 remove “.” from LOAD_PATH, and what's the alternative?
... LOAD_PATH , so this broke them (they reported "no such file to load" for all require statements that based off the project path). Was there a particular justification for doing this?
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Should Javadoc comments be added to the implementation?
...methods that are implementation only (not overrides), sure, why not, especially if they are public.
If you have an overriding situation and you are going to replicate any text, then definitely not. Replication is a surefire way of causing discrepancies. As a result, users would have a different und...
Drop unused factor levels in a subsetted data frame
...tion, a new data frame is created. However, the factor variable retains all of its original levels, even when/if they do not exist in the new dataframe.
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How to run Visual Studio post-build events for debug build only
...figuration)" == "Debug" worked for me. BTW, if you want to do something in all other configs, use if NOT "$(Configuration)" == "Debug".
– Ralf Hundewadt
Jun 29 '17 at 9:46
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Linux/Unix command to determine if process is running?
...s arg vector. Any such approach is doomed to fail sooner or later (you actually admit to that yourself, by saying that more checks are needed). I've added my own recommendation in a separate answer.
– peterh
Oct 3 '13 at 10:41
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Difference between wait() and sleep()
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A wait can be "woken up" by another thread calling notify on the monitor which is being waited on whereas a sleep cannot. Also a wait (and notify) must happen in a block synchronized on the monitor object whereas sleep does not:
Object mon = ...;
synchronized (mon) {
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Read String line by line
...s = myString.split(System.getProperty("line.separator"));
This gives you all lines in a handy array.
I don't know about the performance of split. It uses regular expressions.
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Why create “Implicitly Unwrapped Optionals”, since that implies you know there's a value?
...e two main reasons that one would create an Implicitly Unwrapped Optional. All have to do with defining a variable that will never be accessed when nil because otherwise, the Swift compiler will always force you to explicitly unwrap an Optional.
1. A Constant That Cannot Be Defined During Initializ...
unsigned int vs. size_t
... static array of 8Gb).
The size_t type may be bigger than, equal to, or smaller than an unsigned int, and your compiler might make assumptions about it for optimization.
You may find more precise information in the C99 standard, section 7.17, a draft of which is available on the Internet in pdf fo...