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How do I include negative decimal numbers in this regular expression?
...\d*(\.\d+)?$
I verified it in Rubular with these values:
10.00
-10.00
and both matched as expected.
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What is the difference between C, C99, ANSI C and GNU C?
I have started programming practice on codechef and have been confused by the difference between C and C99. What does C mean here? Is it C89? Check the languages at the bottom of this submit . It contains both C and C99.
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Conditionally use 32/64 bit reference when building in Visual Studio
I have a project that builds in 32/64-bit and has corresponding 32/64-bit dependencies. I want to be able to switch configurations and have the correct reference used, but I don't know how to tell Visual Studio to use the architecture-appropriate dependency.
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Getting the name of a variable as a string
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This glosses over all kinds of problems and caveats and gives the misleading impression that variable name inspection is something people can expect to "just work". For example, if you try to use varname.nameof as the retrieve_name function in the question, you get...
What is a semaphore?
...t should let the guests go in sequentially, but when i tried it out, it's random. Eg. Guest 40 came in first before Guest 39. Is there anything we could do to control this?
– TNA
May 31 '14 at 9:12
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Why doesn't JavaScript support multithreading?
...however use, as was suggested, setTimeout to allow some sort of scheduling and “fake” concurrency. This causes the browser to regain control of the rendering thread, and start the JavaScript code supplied to setTimeout after the given number of milliseconds. This is very useful if you want to al...
What is the “continue” keyword and how does it work in Java?
I saw this keyword for the first time and I was wondering if someone could explain to me what it does.
13 Answers
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Why does the default parameterless constructor go away when you create one with parameters
In C#, C++ and Java, when you create a constructor taking parameters, the default parameterless one goes away. I have always just accepted this fact, but now I've started wondering why.
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How to overcome root domain CNAME restrictions?
...rd with CNAMEs. Use them when renaming hosts, but plan to get rid of them (and inform your users).
Some DNS hosts provide a way to get CNAME-like functionality at the zone apex (the root domain level, for the naked domain name) using a custom record type. Such records include, for example:
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Convert two lists into a dictionary
...onary)
{'a': 1, 'b': 2, 'c': 3}
Voila :-) The pairwise dict constructor and zip function are awesomely useful: https://docs.python.org/3/library/functions.html#func-dict
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