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Regex empty string or email
...can't handle it anyway. Try to find a library routine for matching them. If you only want to solve the practical problem of matching an email address (that is, if you want wrong code that happens to (usually) work), use the regular-expressions.info link someone else submitted.
As for the empty st...
detach all packages while working in R
... value present. One can test for this with names(sessionInfo()$otherPkgs). If it returns NULL, then this is the cause.
– mmfrgmpds
Sep 20 '19 at 16:31
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How to calculate date difference in JavaScript?
I want to calculate date difference in days, hours, minutes, seconds, milliseconds, nanoseconds. How can I do it?
18 Answer...
Where is array's length property defined?
...in the array whereas myArray.length ([]) provides the "capacity". That is, if for myArray = new int[10];, it returns 10. It is not the number of objects you've put in the array.
– wmorrison365
Feb 16 '12 at 13:15
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What is sys.maxint in Python 3?
...As pointed out by others, Python 3's int does not have a maximum size, but if you just need something that's guaranteed to be higher than any other int value, then you can use the float value for Infinity, which you can get with float("inf").
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Placing Unicode character in CSS content value [duplicate]
.../serve the CSS file as UTF-8?
nav a:hover:after {
content: "↓";
}
If that's not good enough, and you want to keep it all-ASCII:
nav a:hover:after {
content: "\2193";
}
The general format for a Unicode character inside a string is \000000 to \FFFFFF – a backslash followed by six hex...
What should every JavaScript programmer know? [closed]
...metimes-ugly details of how JavaScript and the DOM actually work from you. If your aim is to be able to say “I know JavaScript”, then investing a lot of time in a framework is opposed to that.
Here are some JavaScript language features that you should know to grok what it's doing and not get ca...
Environment variable substitution in sed
If I run these commands from a script:
10 Answers
10
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Why is document.write considered a “bad practice”?
...ument.write (henceforth DW) does not work in XHTML
DW does not directly modify the DOM, preventing further manipulation (trying to find evidence of this, but it's at best situational)
DW executed after the page has finished loading will overwrite the page, or write a new page, or not work
DW execute...
SQL variable to hold list of integers
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What if you don't know what the IDs are and that comes from a query? Example: SET @AddressIDs = (SELECT ID FROM address WHERE Account = 1234) This query will return multiple IDs and I get an error saying the subquery returned more...