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Why aren't variables declared in “try” in scope in “catch” or “finally”?
In C# and in Java (and possibly other languages as well), variables declared in a "try" block are not in scope in the corresponding "catch" or "finally" blocks. For example, the following code does not compile:
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Check if a given key already exists in a dictionary
I wanted to test if a key exists in a dictionary before updating the value for the key.
I wrote the following code:
16 Answ...
Python list directory, subdirectory, and files
I'm trying to make a script to list all directory, subdirectory, and files in a given directory.
I tried this:
7 Answers
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SQL “select where not in subquery” returns no results
Disclaimer: I have figured out the problem (I think), but I wanted to add this issue to Stack Overflow since I couldn't (easily) find it anywhere. Also, someone might have a better answer than I do.
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Circular (or cyclic) imports in Python
...ly.
Imports are pretty straightforward really. Just remember the following:
'import' and 'from xxx import yyy' are executable statements. They execute
when the running program reaches that line.
If a module is not in sys.modules, then an import creates the new module
entry in sys.m...
Mimicking sets in JavaScript?
I'm working in JavaScript. I'd like to store a list of unique , unordered string values, with the following properties:
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What's the difference between eval, exec, and compile?
I've been looking at dynamic evaluation of Python code, and come across the eval() and compile() functions, and the exec statement.
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Java: Subpackage visibility?
I have two packages in my project: odp.proj and odp.proj.test . There are certain methods that I want to be visible only to the classes in these two packages. How can I do this?
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Set every cell in matrix to 0 if that row or column contains a 0
Given a NxN matrix with 0s and 1s. Set every row that contains a 0 to all 0 s and set every column that contains a 0 to all 0 s.
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Why are const parameters not allowed in C#?
It looks strange especially for C++ developers. In C++ we used to mark a parameter as const in order to be sure that its state will not be changed in the method. There are also other C++ specific reasons, like passing const ref in order to pass by ref and be sure that state will not be changed. ...