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When to use Cast() and Oftype() in Linq
...ly the elements that can safely be cast to type x.
Cast - will try to cast all the elements into type x. if some of them are not from this type you will get InvalidCastException
EDIT
for example:
object[] objs = new object[] { "12345", 12 };
objs.Cast<string>().ToArray(); //throws InvalidCas...
Maven parent pom vs modules pom
...ructure (pattern #2):
root/
parent-pom/
pom.xml
projectA/
Optionally, you can even add a pom.xml in the trunks directory:
root
|-- parent-pom
| |-- branches
| |-- tags
| `-- trunk
| `-- pom.xml
|-- projectA
| |-- branches
| |-- tags
| `-- trunk
| |-- module1
| ...
Why do I need to do `--set-upstream` all the time?
...he one at origin in the same way as git branch --set-upstream does.
Personally, I think it's a good thing to have to set up that association between your branch and one on the remote explicitly. It's just a shame that the rules are different for git push and git pull.
1 It may sound silly, but ...
Create a variable name with “paste” in R?
...oss: a <- rnorm(1); a - eval(parse(text=paste(a))) does not return 0 usually.
– user10307643
Oct 7 '19 at 13:31
...
Xml configuration versus Annotation based configuration [closed]
...nformation. But if you like JPA (I don't have any expirience with it), by all means, go for it.
In general:
If an annotation provides functionality and acts as a comment in and of itself, and doesn't tie the code down to some specific process in order to function normally without this annotation, ...
difference between throw and throw new Exception()
...w ex; throws the original exception but resets the stack trace, destroying all stack trace information until your catch block.
NEVER write throw ex;
throw new Exception(ex.Message); is even worse. It creates a brand new Exception instance, losing the original stack trace of the exception, as well...
What is LDAP used for?
...e extremely fast read/query performance for a large scale of dataset. Typically you want to store only a small piece of information for each entry. The add/delete/update performance is relatively slower compared with read/query because the assumption is that you don’t do “update” that often.
...
Unique combination of all elements from two (or more) vectors
I am trying to create a unique combination of all elements from two vectors of different size in R.
5 Answers
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Python - List of unique dictionaries
...
If you need all values considered and not just the ID you can use list({str(i):i for i in L}.values()) Here we use str(i) to create a unique string that represents the dictionary which is used to filter the duplicates.
...
Can I combine :nth-child() or :nth-of-type() with an arbitrary selector?
...s of simple selectors.
The :nth-child() pseudo-class counts elements among all of their siblings under the same parent. It does not count only the siblings that match the rest of the selector. Similarly, the :nth-of-type() pseudo-class counts siblings sharing the same element type, which refers to t...