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Meaning of “[: too many arguments” error from if [] (square brackets)
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# if [ hello world == 0 ]
fi
The same will be true for any function call that puts down a string containing spaces or other special characters.
Easy fix
Wrap the variable output in double quotes, forcing it to stay as one string (therefore one argument). For example,
VARIABLE=$(/some/comm...
Why is there no logical xor in JavaScript?
...r. Mainly because it's not useful. Bitwise XOR is extremely useful, but in all my years of programming I have never needed a logical XOR.
If you have two boolean variables you can mimic XOR with:
if (a != b)
With two arbitrary variables you could use ! to coerce them to boolean values and then u...
Show percent % instead of counts in charts of categorical variables
...for 'ggplot count vs percentage histogram' so hopefully this helps distill all the information currently housed in comments on the accepted answer.
Remark: If hp is not set as a factor, ggplot returns:
share
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Test parameterization in xUnit.net similar to NUnit
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xUnit offers a way to run parameterized tests through something called data theories. The concept is equivalent to the one found in NUnit but the functionality you get out of the box is not as complete.
Here's an example:
[Theory]
[InlineData("Foo")]
[InlineData(9)]
[InlineData(true)]
pu...
Is #pragma once a safe include guard?
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It shouldn't be any slower at all (with GCC anyway).
– Jason Coco
Apr 24 '09 at 21:07
54
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What's so bad about Template Haskell?
...on for avoiding Template Haskell is that it as a whole isn't type-safe, at all, thus going against much of "the spirit of Haskell." Here are some examples of this:
You have no control over what kind of Haskell AST a piece of TH code will generate, beyond where it will appear; you can have a value ...
C++, copy set to vector
...hold the input range.
std::back_inserter creates an output iterator that calls push_back on a container for each element, so each element is inserted into the container. Alternatively, you could have created a sufficient number of elements in the std::vector to hold the range being copied:
std::v...
How to get the current working directory in Java?
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@ubuntudroid: that's why i mentioned specifically that it will print the path from where the application had initialized. My guess the thread starter directly run the jar/program after starting commnad prompt (which is basically at C:\WINDOWS\system32). I hope you under...
Make a URL-encoded POST request using `http.NewRequest(…)`
...m"
resource := "/user/"
data := url.Values{}
data.Set("name", "foo")
data.Set("surname", "bar")
u, _ := url.ParseRequestURI(apiUrl)
u.Path = resource
urlStr := u.String() // "https://api.com/user/"
client := &http.Client{}
r, _ := http.NewRequest(http.Method...
'AND' vs '&&' as operator
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If you use AND and OR, you'll eventually get tripped up by something like this:
$this_one = true;
$that = false;
$truthiness = $this_one and $that;
Want to guess what $truthiness equals?
If you said false... bzzzt, sorry, wrong!
$truthiness above has the ...