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Understanding repr( ) function in Python
... When you call for example repr(x) the interpreter puts 'foo' instead of x and then calls repr('foo').
>>> repr(x)
"'foo'"
>>> x.__repr__()
"'foo'"
repr actually calls a magic method __repr__ of x, which gives the string containing the representation of the value 'foo' assigned ...
Can I extend a class using more than 1 class in PHP?
...nd it for use in production, one can use ReflectionClass to access private and protected methods.
– Denis V
Dec 18 '13 at 19:21
2
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With Mercurial, how can I “compress” a series of changesets into one before pushing?
Let's say I have a local and a remote Mercurial repository. Now, I start working on a feature. I work on it, and when I think it's done, I commit the changeset. Testing it a bit more, I find that I could further improve this feature by tweaking something in the code. I make the change and commit. 20...
Does Typescript support the ?. operator? (And, what's it called?)
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Update: it is supported as of TypeScript 3.7 and called Optional chaining: https://www.typescriptlang.org/docs/handbook/release-notes/typescript-3-7.html#optional-chaining
I can't find any reference to it whatsoever in the TypeScript language specification.
As far as ...
What is the rationale behind having companion objects in Scala?
...eton) for a class is needed? Why would I want to create a class, say Foo and also create a companion object for it?
7 Ans...
Override valueof() and toString() in Java enum
...d (getEnum in the sample code below) which returns the value that you need and change your client to use this method instead.
public enum RandomEnum {
StartHere("Start Here"),
StopHere("Stop Here");
private String value;
RandomEnum(String value) {
this.value = value;
...
Check existence of directory and create if doesn't exist
...ry(s). What I've written below will check for the existence of a directory and move into it, or create the directory and then move into it. Is there a better way to approach this?
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Detect and exclude outliers in Pandas data frame
I have a pandas data frame with few columns.
17 Answers
17
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How to extract the first two characters of a string in shell scripting?
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Probably the most efficient method, if you're using the bash shell (and you appear to be, based on your comments), is to use the sub-string variant of parameter expansion:
pax> long="USCAGol.blah.blah.blah"
pax> short="${long:0:2}" ; echo "${short}"
US
This will set short to be the f...
displayname attribute vs display attribute
What is difference between DisplayName attribute and Display attribute in ASP.NET MVC?
4 Answers
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