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When would anyone use a union? Is it a remnant from the C-only days?
I have learned but don't really get unions. Every C or C++ text I go through introduces them (sometimes in passing), but they tend to give very few practical examples of why or where to use them. When would unions be useful in a modern (or even legacy) case? My only two guesses would be programming ...
Advantage of switch over if-else statement
...-depth study of the assembly code generated by a switch. Very enlightning: http://lazarenko.me/switch/
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Fastest way to get the first object from a queryset in django?
...eturn None if there aren't any. There are lots of ways to do this which all work. But I'm wondering which is the most performant.
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Filter rows which contain a certain string
...verse)
# The data. Data expo 09. ASA Statistics Computing and Graphics
# http://stat-computing.org/dataexpo/2009/the-data.html
df <- read_csv("Downloads/2008.csv")
print(dim(df))
# [1] 7009728 29
benchmark(
"str_detect" = {df %>% filter(str_detect(Dest, 'MCO|BWI'))},
"grepl" = {df ...
How do you do a limit query in JPQL or HQL?
...QL Parser, and it's a lot less forgiving.
I think Query.setMaxResults() really is your only option.
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How do you run your own code alongside Tkinter's event loop?
...tion for the after method:
def after(self, ms, func=None, *args):
"""Call function once after given time.
MS specifies the time in milliseconds. FUNC gives the
function which shall be called. Additional parameters
are given as parameters to the function call. Return
identifier...
Is there a TRY CATCH command in Bash
... writing a shell script and need to check that a terminal app has been installed. I want to use a TRY/CATCH command to do this unless there is a neater way.
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Will the base class constructor be automatically called?
... age of customer be 2? It seems like the base class's constructor will be called no matter what. If so, why do we need to call base at the end sometimes?
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Read text file into string array (and write)
...eUploader: {
brandingHtml: "Powered by \u003ca href=\"https://imgur.com/\"\u003e\u003csvg class=\"svg-icon\" width=\"50\" height=\"18\" viewBox=\"0 0 50 18\" fill=\"none\" xmlns=\"http://www.w3.org/2000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 4...
Remove empty array elements
...back is supplied, all entries of input equal to FALSE will be removed." -- http://php.net/manual/en/function.array-filter.php
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