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JavaScript for…in vs for
Do you think there is a big difference in for...in and for loops? What kind of "for" do you prefer to use and why?
23 Answe...
Difference between Build Solution, Rebuild Solution, and Clean Solution in Visual Studio?
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Build solution will perform an incremental build: if it doesn't think it needs to rebuild a project, it won't. It may also use partially-built bits of the project if they haven't changed (I don't know how far it takes this)
Rebuild solution will clean and then build the solution f...
How do I get the file extension of a file in Java?
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@BrainSlugs83 So what does mean "tar"?
– TuGordoBello
Mar 23 '16 at 14:42
31
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data.table vs dplyr: can one do something well the other can't or does poorly?
... the moment allows one to modify/update columns by reference (note that we don't need to re-assign the result back to a variable).
# sub-assign by reference, updates 'y' in-place
DT[x >= 1L, y := NA]
But dplyr will never update by reference. The dplyr equivalent would be (note that the result ...
How to check if my string is equal to null?
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if (myString != null && !myString.isEmpty()) {
// doSomething
}
As further comment, you should be aware of this term in the equals contract:
From Object.equals(Object):
For any non-null reference value x, x.equals(null) should return false.
The way to compare wit...
Schema for a multilanguage database
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What do you think about having a related translation table for each translatable table?
CREATE TABLE T_PRODUCT (pr_id int, PRICE NUMBER(18, 2))
CREATE TABLE T_PRODUCT_tr (pr_id INT FK, languagecode varchar, pr_name text, pr_descr...
How do I migrate a model out of one django app and into a new one?
... it. I realize now that one of these models should be in a separate app. I do have south installed for migrations, but I don't think this is something it can handle automatically. How can I migrate one of the models out of the old app into a new one?
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List comprehension in Ruby
To do the equivalent of Python list comprehensions, I'm doing the following:
17 Answers
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How do you represent a graph in Haskell?
...e Knot to get around this, but that makes my brain hurt (because I haven't done much of it yet). I've done more of my substantial programming in Mercury than Haskell so far, and Mercury is strict so knot-tying doesn't help.
Usually when I've run into this before I've just resorted to additional ind...
How do I format a number with commas in T-SQL?
...SQL Server, this issue has never come up since most of the time I would be doing formatting at the presentation layer, but in this case the T-SQL result in SSMS is the presentation.
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