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Accessing last x characters of a string in Bash
... line:
$ foo=1234567890
$ echo $foo | grep -o ...$
890
To make it optionally get the 1 to 3 last chars, in case of strings with less than 3 chars, you can use egrep with this regex:
$ echo a | egrep -o '.{1,3}$'
a
$ echo ab | egrep -o '.{1,3}$'
ab
$ echo abc | egrep -o '.{1,3}$'
abc
$ echo abcd ...
Why not infer template parameter from constructor?
...
This is actually a great point which I never considered. I don't see any way around the fact that the pointer would have to be type specific (i.e. it would have to be MyClass<string>* pm). If that's the case, then all you would end...
Detecting an “invalid date” Date instance in JavaScript
...
Here's how I would do it:
if (Object.prototype.toString.call(d) === "[object Date]") {
// it is a date
if (isNaN(d.getTime())) { // d.valueOf() could also work
// date is not valid
} else {
// date is valid
}
} else {
// not a date
}
Update [2018-05-31]: If you...
It is more efficient to use if-return-return or if-else-return?
...the if condition is false anyway.
Note that Python supports a syntax that allows you to use only one return statement in your case:
return A+1 if A > B else A-1
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Create new tmux session from inside a tmux session
... Thanks for the very complete answer, this answered a few of my questions all at once!
– mdekkers
Jun 1 '18 at 4:33
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Count, size, length…too many choices in Ruby?
...1
In the case where you don't provide a parameter to count it has basically the same effect as calling length. There can be a performance difference though.
We can see from the source code for Array that they do almost exactly the same thing. Here is the C code for the implementation of array.l...
Passing Objects By Reference or Value in C#
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Objects aren't passed at all. By default, the argument is evaluated and its value is passed, by value, as the initial value of the parameter of the method you're calling. Now the important point is that the value is a reference for reference types - ...
Showing empty view when ListView is empty
... when the ListView is not empty. I thought the ListView would automatically detect when to show the empty view.
11 Answ...
How to use regex with find command?
.... For example 81397018-b84a-11e0-9d2a-001b77dc0bed.jpg. I want to find out all these images using "find" command:
7 Answers...
JavaScript OR (||) variable assignment explanation
...otcha' which is that the last one will always get assigned even if they're all undefined, null or false. Setting something you know isn't false, null, or undefined at the end of the chain is a good way to signal nothing was found.
– Erik Reppen
Aug 29 '11 at 1...
