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How to check if a file exists in Go?
Go's standard library does not have a function solely intended to check if a file exists or not (like Python's os.path.exists ). What is the idiomatic way to do it?
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SQL - find records from one table which don't exist in another
...s, with varying efficiency, depending on how good your query optimiser is, and the relative size of your two tables:
This is the shortest statement, and may be quickest if your phone book is very short:
SELECT *
FROM Call
WHERE phone_number NOT IN (SELECT phone_number FROM Phone_book)
alte...
Can someone explain mappedBy in JPA and Hibernate?
I am new to hibernate and need to use one-to-many and many-to-one relations. It is a bi-directional relationship in my objects, so that I can traverse from either direction. mappedBy is the recommended way to go about it, however, I couldn't understand it. Can someone explain:
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How to make a div fill a remaining horizontal space?
I have 2 divs: one in the left side and one in the right side of my page. The one in the left side has fixed width and I want the one of the right side to fill the remaining space.
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Scanner vs. StringTokenizer vs. String.Split
I just learned about Java's Scanner class and now I'm wondering how it compares/competes with the StringTokenizer and String.Split. I know that the StringTokenizer and String.Split only work on Strings, so why would I want to use the Scanner for a String? Is Scanner just intended to be one-stop-shop...
Given a view, how do I get its viewController?
...r, because that would break MVC principles.
The controller, on the other hand, knows which view it's responsible for (self.view = myView), and usually, this view delegates methods/events for handling to the controller.
Typically, instead of a pointer to your view, you should have a pointer to your...
How to enable Bootstrap tooltip on disabled button?
I need to display a tooltip on a disabled button and remove it on an enabled button. Currently, it works in reverse.
18 Ans...
What are Long-Polling, Websockets, Server-Sent Events (SSE) and Comet?
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In the examples below the client is the browser and the server is the webserver hosting the website.
Before you can understand these technologies, you have to understand classic HTTP web traffic first.
Regular HTTP:
A client requests a webpage from a server.
The server...
How do you produce a .d.ts “typings” definition file from an existing JavaScript library?
I'm using a lot of libraries both my own and 3rd party. I see the "typings" directory contains some for Jquery and WinRT... but how are they created?
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Using regular expressions to parse HTML: why not?
...ossible with regular expressions, since it depends on matching the opening and the closing tag which is not possible with regexps.
Regular expressions can only match regular languages but HTML is a context-free language and not a regular language (As @StefanPochmann pointed out, regular languages a...