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How can I print a circular structure in a JSON-like format?
... to toss whatever circular references exist and send whatever can be stringified. How do I do that?
25 Answers
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How to remove leading and trailing whitespace in a MySQL field?
... only removes spaces - not tabs, formfeeds etc. A combination of TRIMs specifying other whitespace characters may provide a limited improvement e.g. TRIM(BOTH '\r' FROM TRIM(BOTH '\n' FROM TRIM(BOTH '\f' FROM TRIM(BOTH '\t' FROM TRIM(txt))))). But the problem with this approach is only a single char...
Is there a “not in” operator in JavaScript for checking object properties?
Is there any sort of "not in" operator in JavaScript to check if a property does not exist in an object? I couldn’t find anything about this around Google or Stack Overflow. Here’s a small snippet of code I’m working on where I need this kind of functionality:
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Fastest way to check if a value exists in a list
What is the fastest way to know if a value exists in a list (a list with millions of values in it) and what its index is?
1...
Hidden Features of JavaScript? [closed]
... pop(), push(), slice() and so forth. (You can convert it to a real array if you want: "var argArray = Array.prototype.slice.call(arguments);" )
– Jacob Mattison
Jan 26 '09 at 21:37
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How expensive is RTTI?
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Regardless of compiler, you can always save on runtime if you can afford to do
if (typeid(a) == typeid(b)) {
B* ba = static_cast<B*>(&a);
etc;
}
instead of
B* ba = dynamic_cast<B*>(&a);
if (ba) {
etc;
}
The former involves only one comparison of s...
How to check if a function exists on a SQL database
I need to find out if a function exists on a database, so that I can drop it and create it again. It should basically be something like the following code that I use for stored procedures:
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SQL Server - stop or break execution of a SQL script
...te 0, Line 0
A severe error occurred on the current command. The results, if any, should be discarded.
Notice that 'ho' is not printed.
CAVEATS:
This only works if you are logged in as admin ('sysadmin' role), and also leaves you with no database connection.
If you are NOT logged in as admin, ...
Check whether a path is valid
I am just wondering: I am looking for a way to validate if a given path is valid.
(Note: I do not want to check if a file is existing! I only want to proof the validity of the path - So if a file could possibly exists at the location) .
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Check existence of input argument in a Bash shell script
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It is:
if [ $# -eq 0 ]
then
echo "No arguments supplied"
fi
The $# variable will tell you the number of input arguments the script was passed.
Or you can check if an argument is an empty string or not like:
if [ -z "$1" ]
t...