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What does void mean in C, C++, and C#?
...void in the argument list is optional. However, in C, it is NOT optional: foo() means it takes any number of parameters of any type, whereas foo(void) means it takes zero parameters.
– Adam Rosenfield
Jun 28 '09 at 5:00
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How to capture no file for fs.readFileSync()?
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Basically, fs.readFileSync throws an error when a file is not found. This error is from the Error prototype and thrown using throw, hence the only way to catch is with a try / catch block:
var fileContents;
try {
fileContents =...
Are there any downsides to passing structs by value in C, rather than passing a pointer?
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For small structs (eg point, rect) passing by value is perfectly acceptable. But, apart from speed, there is one other reason why you should be careful passing/returning large structs by value: Stack space.
A lot of C programming ...
warning: incompatible implicit declaration of built-in function ‘xyz’
...;
}
Compiled like this on Fedora 17 Linux 64 bit with gcc:
el@defiant ~/foo2 $ gcc -o n n2.c
n2.c: In function ‘main’:
n2.c:2:3: warning: incompatible implicit declaration of built-in
function ‘exit’ [enabled by default]
el@d...
String literals: Where do they go?
I am interested in where string literals get allocated/stored.
8 Answers
8
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insert vs emplace vs operator[] in c++ map
...ing value_type or make_pair . While there is a lot of information about all of them and questions about particular cases, I still can't understand the big picture.
So, my two questions are:
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How to replace a string in a SQL Server Table Column
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I'd typically add where path like '%oldstring%' if there was a lot of data.
– Derek Tomes
Nov 2 '15 at 20:48
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querySelector and querySelectorAll vs getElementsByClassName and getElementById in JavaScript
...w what exactly is the difference between querySelector and querySelectorAll against getElementsByClassName and getElementById ?
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How to trim whitespace from a Bash variable?
... '
echo -e "length(FOO)==${#FOO}"
# > length(FOO)==16
How to remove all whitespace (denoted by [:space:] in tr):
FOO=' test test test '
FOO_NO_WHITESPACE="$(echo -e "${FOO}" | tr -d '[:space:]')"
echo -e "FOO_NO_WHITESPACE='${FOO_NO_WHITESPACE}'"
# > FOO_NO_WHITESPACE='testtesttest'
echo ...
What's an elegant way to conditionally add a class to an HTML element in a view?
...sses where the boolean value evaluated to true.
Sample Usage
class_names(foo: true, bar: false, baz: some_truthy_variable)
# => "foo baz"
Other Use Cases
This helper can be used within ERB tags or with Rails helpers such as link_to.
<div class="<%= class_string(ok: @success) %>">...