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Determine what attributes were changed in Rails after_save callback?
I'm setting up an after_save callback in my model observer to send a notification only if the model's published attribute was changed from false to true. Since methods such as changed? are only useful before the model is saved, the way I'm currently (and unsuccessfully) trying to do so is as fol...
Can I use a binary literal in C or C++?
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You can use BOOST_BINARY while waiting for C++0x. :) BOOST_BINARY arguably has an advantage over template implementation insofar as it can be used in C programs as well (it is 100% preprocessor-driven.)
To do the converse (i.e. print out a ...
How to create a checkbox with a clickable label?
...can explain the comment @John left please do, because it makes no sense at all to me.
– Wesley Murch
Jul 30 '15 at 13:45
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Setting custom UITableViewCells height
...ulate the cell height needed and return that calculated value here to make all cells visible
– Vinayak GH
Jan 11 '16 at 7:39
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How do I print a double value with full precision using cout?
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Is the really the right answer? When I manually use a high number, I can print out as many as 51 digits of approximated e, but with cout.precision(numeric_limits<double>::digits10 + 2); I only get 16....
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Disable all table constraints in Oracle
How can I disable all table constrains in Oracle with a single command?
This can be either for a single table, a list of tables, or for all tables.
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LINQ - Full Outer Join
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I don't know if this covers all cases, logically it seems correct. The idea is to take a left outer join and right outer join then take the union of the results.
var firstNames = new[]
{
new { ID = 1, Name = "John" },
new { ID = 2, Name = "Sue"...
In Python, if I return inside a “with” block, will the file still close?
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@RikPoggi os._exit is sometimes used - it exits the Python process without calling cleanup handlers.
– Acumenus
Oct 8 '16 at 6:25
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Class vs. static method in JavaScript
... instantiate an object from that function using the new keyword which will allow you to create something similar to a class in a standard OOP language.
I'd suggest ignoring __proto__ most of the time because it has poor cross browser support, and instead focus on learning about how prototype works....
Merge Images Side by Side(Horizontally)
...hips with the montage utility. Montage will append each image side-by-side allowing you to adjust spacing between each image (-geometry), and the general layout (-tile).
montage [0-5].png -tile 5x1 -geometry +0+0 out.png
Other examples can be found on Montage Usage page
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