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What's the difference between QMainWindow, QWidget and QDialog?
...wn as a window. It will always appear in a window, and has functions to make it work well with common buttons on dialogs (accept, reject, etc.).
QMainWindow is designed around common needs for a main window to have. It has predefined places for a menu bar, a status bar, a toolbar, and other widge...
Is there a command to list all Unix group names? [closed]
I know there is the /etc/group file that lists all users groups.
3 Answers
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Is there a more elegant way of adding an item to a Dictionary safely?
I need to add key/object pairs to a dictionary, but I of course need to first check if the key already exists otherwise I get a " key already exists in dictionary " error. The code below solves this but is clunky.
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__getattr__ on a module
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A while ago, Guido declared that all special method lookups on
new-style classes bypass __getattr__ and __getattribute__. Dunder methods had previously worked on modules - you could, for example, use a module as a context manager simply by defining __enter__ and __exit__, before ...
When is .then(success, fail) considered an antipattern for promises?
I had a look at the bluebird promise FAQ , in which it mentions that .then(success, fail) is an antipattern . I don't quite understand its explanation as for the try and catch.
What's wrong with this the following?
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Using str_replace so that it only acts on the first match?
...h in the $subject . Is there an easy solution to this, or do I need a hacky solution?
22 Answers
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How to show vertical line to wrap the line in Vim?
...rtunately vim has no mechanism to display a vertical line after a column like you want (unlike, say, TextMate). However, there are alternative visual indicators that you can use to show that a line is too long.
Here's what I use (you can put this in your .vimrc):
nnoremap <Leader>H :call<...
What should go into an .h file?
...to provide the information that will be needed in multiple files. Things like class declarations, function prototypes, and enumerations typically go in header files. In a word, "definitions".
Code files (.cpp) are designed to provide the implementation information that only needs to be known in one...
Difference Between One-to-Many, Many-to-One and Many-to-Many?
Ok so this is probably a trivial question but I'm having trouble visualizing and understanding the differences and when to use each. I'm also a little unclear as to how concepts like uni-directional and bi-directional mappings affect the one-to-many/many-to-many relationships. I'm using Hibernate ri...
Check if Internet Connection Exists with Javascript? [duplicate]
How do you check if there is an internet connection using Javascript? That way I could have some conditionals saying "use the google cached version of JQuery during production, use either that or a local version during development, depending on the internet connection".
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