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Utility classes are evil? [closed]
... good object-oriented design, most classes should represent a single thing and all of its attributes and operations. If you are operating on a thing, that method should probably be a member of that thing.
However, there are times when you can use utility classes to group a number of methods togethe...
How can I check if an element exists in the visible DOM?
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It seems some people are landing here, and simply want to know if an element exists (a little bit different to the original question).
That's as simple as using any of the browser's selecting method, and checking it for a truthy value (generally).
F...
Why can't a text column have a default value in MySQL?
If you try to create a TEXT column on a table, and give it a default value in MySQL, you get an error (on Windows at least). I cannot see any reason why a text column should not have a default value. No explanation is given by the MySQL documentation. It seems illogical to me (and somewhat frustrati...
Center a popup window on screen?
...: It will also work on windows that aren't maxed out to the screen's width and height now thanks to @Frost!
If you're on dual monitor, the window will center horizontally, but not vertically... use this function to account for that.
const popupCenter = ({url, title, w, h}) => {
// Fixes dua...
Handling JSON Post Request in Go
So I have the following, which seems incredibly hacky, and I've been thinking to myself that Go has better designed libraries than this, but I can't find an example of Go handling a POST request of JSON data. They are all form POSTs.
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Can anyone explain what JSONP is, in layman terms? [duplicate]
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Preface:
This answer is over six years old. While the concepts and application of JSONP haven't changed
(i.e. the details of the answer are still valid), you should
look to use CORS where possible
(i.e. your server or
API supports it, and the
browser support is adequate),
as JSONP has in...
How do I directly modify a Google Chrome Extension File? (.CRX)
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I searched it in Google and I found this:
The Google Chrome Extension file type is CRX. It is essentially a compression format. So if you want to see what is behind an extension, the scripts and the code, just change the file-type from “CRX” t...
Why is sed not recognizing \t as a tab?
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Not all versions of sed understand \t. Just insert a literal tab instead (press Ctrl-V then Tab).
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Load “Vanilla” Javascript Libraries into Node.js
...ry that I found.) But these libraries are just straightforward .js files and not "Node.js libraries".
7 Answers
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Selecting/excluding sets of columns in pandas [duplicate]
...passed as argument removed.
Here, the result is used to remove columns B and D from df:
df2 = df[df.columns.difference(['B', 'D'])]
Note that it's a set-based method, so duplicate column names will cause issues, and the column order may be changed.
Advantage over drop: you don't create a cop...