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Why are local variables not initialized in Java?
...ulation. So its the programmer's decision to set the value of the variable and it should not take a default value. If the programmer, by mistake, did not initialize a local variable and it take default value, then the output could be some unexpected value. So in case of local variables, the compiler...
How to find the length of a string in R
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nchar(YOURSTRING)
you may need to convert to a character vector first;
nchar(as.character(YOURSTRING))
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How can I add new keys to a dictionary?
...values at the same time, as long as the keys are strings (since kwargs are converted to strings). dict.update can also take another dictionary, but I personally prefer not to explicitly create a new dictionary in order to update another one.
– bgusach
Feb 13 '1...
Why does writeObject throw java.io.NotSerializableException and how do I fix it?
I have this exception and I don't understand why it would be thrown or, how I should handle it.
3 Answers
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How do I bind a WPF DataGrid to a variable number of columns?
...ableColumnsPropertyChanged: 1. Check dataGrid for null before accessing it and throw an exception with good explanation about binding only to DataGrid. 2. Check e.OldValue for null and unsubscribe from CollectionChanged event to prevent memory leaks. Just for your convince.
– M...
How do you attach a new pull request to an existing issue on github?
...s to the master branch of his repo. This is the command you would write to convert your previous Issue into a Pull Request for this situation:
$ http --auth "smparkes" \
POST \
https://api.github.com/repos/technoweenie/faraday/pulls \
issue=15 head=smparkes:synchrony base=maste...
How do I check if a given string is a legal/valid file name under Windows?
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2nd piece of code doesn't compile. "Cannot convert from char[] to string
– Paul Hunt
Apr 25 '14 at 12:03
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How to escape special characters in building a JSON string?
...ncoding library to use. If you simply use language or library functions to convert things to and from JSON, you'll never even need to know JSON's escaping rules. This is what the misguided question asker here ought to have done.
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Why does Lua have no “continue” statement?
I have been dealing a lot with Lua in the past few months, and I really like most of the features but I'm still missing something among those:
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Why does the expression 0 < 0 == 0 return False in Python?
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I believe Python has special case handling for sequences of relational operators to make range comparisons easy to express. It's much nicer to be able to say 0 < x <= 5 than to say (0 < x) and (x <= 5).
These are called chained comparisons. And th...