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xpath find if node exists
Using a xpath query how do you find if a node (tag) exists at all?
6 Answers
6
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Should I put the Google Analytics JS in the or at the end of ?
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Yes, it's fine to do so; I actually have a mix, but have mostly migrated to putting it on the top for the reasons mentioned.
– Chris Arguin
Jul 4 '10 at 12:46
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JavaScript math, round to two decimal places [duplicate]
...https://stackoverflow.com/a/32605063/1726511 Which seems to work well with all the tests I've tried.
There is one minor modification required though, the function in the answer linked above returns whole numbers when it rounds to one, so for example 99.004 will return 99 instead of 99.00 which isn't...
MySQL “Group By” and “Order By”
...olumns in a SELECT with a GROUP BY clause is non-standard. MySQL will generally return the values of the first row it finds and discard the rest. Any ORDER BY clauses will only apply to the returned column value, not to the discarded ones.
IMPORTANT UPDATE
Selecting non-aggregate columns used to wor...
Can I set background image and opacity in the same property?
... Yeah, the big problem with a PNG is the size. It is likely going to be really large. Now that we can specify opacity: ... in all browsers, it way better!
– Alexis Wilke
Jul 1 '17 at 23:49
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How to directly initialize a HashMap (in a literal way)?
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All Versions
In case you happen to need just a single entry: There is Collections.singletonMap("key", "value").
For Java Version 9 or higher:
Yes, this is possible now. In Java 9 a couple of factory methods have been added...
Do spurious wakeups in Java actually happen?
...hread_cond_wait() function in Linux is implemented using the futex system call. Each blocking system call on Linux returns abruptly with EINTR when the process receives a signal. ... pthread_cond_wait() can't restart the waiting because it may miss a real wakeup in the little time it was outside the...
What's the difference(s) between .ToList(), .AsEnumerable(), AsQueryable()?
...or example, we need to use one of our own methods in a query we would typically write something like
var query = context.Observations.Select(o => o.Id)
.AsEnumerable().Select(x => MySuperSmartMethod(x))
ToList – which converts an IEnumerable<T> to a List<T> ...
Are strongly-typed functions as parameters possible in TypeScript?
...f the types of its argument and its return type. Here we specify that the callback parameter's type must be "function that accepts a number and returns type any":
class Foo {
save(callback: (n: number) => any) : void {
callback(42);
}
}
var foo = new Foo();
var strCallback = (re...
git merge: apply changes to code that moved to a different file
...s copy has been done in a commit that we name commit CP.
You want to apply all your local changes, commits A and B below, that were made on original.txt, to the new file copy.txt.
---- X -----CP------ (master)
\
`--A---B--- (local)
Create a throwaway branch move at the starting p...