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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 ...
psql - save results of command to a file
I'm using psql's \dt to list all tables in a database and I need to save the results.
10 Answers
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What happens when a computer program runs?
I know the general theory but I can't fit in the details.
4 Answers
4
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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...
Python integer incrementing with ++ [duplicate]
I've always laughed to myself when I've looked back at my VB6 days and thought, "What modern language doesn't allow incrementing with double plus signs?":
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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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Create timestamp variable in bash script
I am trying to create a timestamp variable in a shell script to make the logging a little easier. I want to create the variable at the beginning of the script and have it print out the current time whenever I issue echo $timestamp . It proving to be more difficult then I thought. Here are some thin...
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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