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What is the difference between string primitives and String objects in JavaScript?
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JavaScript has two main type categories, primivites and objects.
var s = 'test';
var ss = new String('test');
The single quote/double quote patterns are identical in terms of functionality. That aside, the behaviour you are trying to name is called auto-boxing. So what actually ...
Merging: Hg/Git vs. SVN
I often read that Hg (and Git and...) are better at merging than SVN but I have never seen practical examples of where Hg/Git can merge something where SVN fails (or where SVN needs manual intervention). Could you post a few step-by-step lists of branch/modify/commit/...-operations that show where S...
How to make good reproducible pandas examples
Having spent a decent amount of time watching both the r and pandas tags on SO, the impression that I get is that pandas questions are less likely to contain reproducible data. This is something that the R community has been pretty good about encouraging, and thanks to guides like this , newc...
How to use the TextWatcher class in Android?
Can anyone tell me how to mask the substring in EditText or how to change EditText substring input to password type or replace by another character like this 123xxxxxxxxx3455
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Remove an entire column from a data.frame in R
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6 chr1 exon
As pointed out in the comments, here are some other possibilities:
Data[2] <- NULL # Wojciech Sobala
Data[[2]] <- NULL # same as above
Data <- Data[,-2] # Ian Fellows
Data <- Data[-2] # same as above
You can remove multiple columns via:
Data[1:2] <- list(N...
How to document class attributes in Python? [closed]
I'm writing a lightweight class whose attributes are intended to be publicly accessible, and only sometimes overridden in specific instantiations. There's no provision in the Python language for creating docstrings for class attributes, or any sort of attributes, for that matter. What is the expec...
JavaScript - cannot set property of undefined
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you never set d[a] to any value.
Because of this, d[a] evaluates to undefined, and you can't set properties on undefined.
If you add d[a] = {} right after d = {} things should work as expected.
Alternatively, you could use an object initializer:
d[a] = {
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Is Ruby pass by reference or by value?
@user object adds errors to the lang_errors variable in the update_lanugages method.
when I perform a save on the @user object I lose the errors that were initially stored in the lang_errors variable.
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Entity Framework - Invalid Column Name '*_ID"
I've narrowed this down to some issue between Code First and Database first EF, but I'm not sure how to fix it. I'll try to be as clear as I can, but I honestly am missing some of the understanding here myself. This is Entity Framework 4.4
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What does enctype='multipart/form-data' mean?
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When you make a POST request, you have to encode the data that forms the body of the request in some way.
HTML forms provide three methods of encoding.
application/x-www-form-urlencoded (the default)
multipart/form-data
text/plain
Work was being done on adding application/json, but that has...