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Split string in Lua?
...to do a simple split of a string, but there doesn't seem to be a function for this, and the manual way I tested didn't seem to work. How would I do it?
...
R object identification
I am often ending up with a function producing output for which I don't understand the output data type. I'm expecting a list and it ends up being a list of lists or a data frame or something else. What's a good method or workflow for figuring out the output data type when first using a function?
...
What is a 'Closure'?
...riable has a scope. Generally, local variables exist only within the block or function in which you declare them.
function() {
var a = 1;
console.log(a); // works
}
console.log(a); // fails
If I try to access a local variable, most languages will look for it in the current scope, then up ...
Default value of BOOL
...x; // <--- no default value
It is initialized to garbage.
However, for a BOOL ivar, it will be initialized to NO, as the whole instance is filled with 0 on initialization.
(Note: When ARC is enabled, local object pointers will always be have a default value nil, but local variables of non-ob...
What are Transient and Volatile Modifiers?
...serialized, the field will be initialized to the default value; i.e. null for a reference type, and zero or false for a primitive type. Note that the JLS (see 8.3.1.3) does not say what transient means, but defers to the Java Object Serialization Specification. Other serialization mechanisms may pay...
What does enumerable mean?
I was directed to MDN's for..in page when it said, "for..in Iterates over the enumerable properties of an object."
8 Answ...
Variable interpolation in the shell
...
Use
"$filepath"_newstap.sh
or
${filepath}_newstap.sh
or
$filepath\_newstap.sh
_ is a valid character in identifiers. Dot is not, so the shell tried to interpolate $filepath_newstap.
You can use set -u to make the shell exit with an error when yo...
Pythonic way to check if a list is sorted or not
Is there a pythonic way to check if a list is already sorted in ASC or DESC
23 Answers
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How to copy a file to a remote server in Python using SCP or SSH?
...l the scp bash command (it copies files over SSH) with subprocess.run:
import subprocess
subprocess.run(["scp", FILE, "USER@SERVER:PATH"])
#e.g. subprocess.run(["scp", "foo.bar", "joe@srvr.net:/path/to/foo.bar"])
If you're creating the file that you want to send in the same Python program, you'll...
What happens to a github student account's repositories at the end of 2 years?
... using my university email address. I'm planning to use the private repositories for some class projects this semester, but I'm wondering what will happen to those repositories at the end of 2 years when my free student upgrade expires. I'm assuming it's the same thing that happens when you downgrad...