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C++ const map element access
...ut_of_range exception. (This is similar to the behaviour of at() for deque and vector.)
Because of this behaviour it makes sense for there to be a const overload of at(), unlike operator[] which always has the potential to change the map.
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Difference between .keystore file and .jks file
I have tried to find the difference between .keystore files and .jks files, yet I could not find it. I know jks is for "Java keystore" and both are a way to store key/value pairs.
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Which timestamp type should I choose in a PostgreSQL database?
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First off, PostgreSQL’s time handling and arithmetic is fantastic and Option 3 is fine in the general case. It is, however, an incomplete view of time and timezones and can be supplemented:
Store the name of a user’s time zone as a user preference (e....
Vim: Creating parent directories on save
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augroup BWCCreateDir
autocmd!
autocmd BufWritePre * if expand("<afile>")!~#'^\w\+:/' && !isdirectory(expand("%:h")) | execute "silent! !mkdir -p ".shellescape(expand('%:h'), 1) | redraw! | endif
augroup END
Note the conditions: expand("<afile>")!~#'^\w\+:/' wil...
How to play with Control.Monad.Writer in haskell?
I'm new to functional programming and recently learning at Learn You a Haskell , but when I went through this chapter , I got stuck with the program below:
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Perform Segue programmatically and pass parameters to the destination view
...ue is triggered.
The prepareForSegue:sender: method is called in any case and this is where you pass your parameters across.
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difference and when to use getApplication(), getApplicationContext(), getBaseContext() and someClass
I'm new to android and I'm trying to understand the difference between getApplication() , getApplicationContext( ), getBaseContext() , getContext() and someClass.this and especially when to use the these methods in the following code lines:
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JavaScript: How to pass object by value?
... properties added to o will be available from obj if they're not shadowed, and all objects that have o in the prototype chain will see the same updates to o.
Also, if obj has a property that references another object, like an Array, you'll need to be sure to shadow that object before adding members...
When is del useful in python?
I can't really think of any reason why python needs the del keyword (and most languages seem to not have a similar keyword). For instance, rather than deleting a variable, one could just assign None to it. And when deleting from a dictionary, a del method could be added.
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What's the algorithm to calculate aspect ratio?
...8:1.
If so, what you need to do is find the greatest common divisor (GCD) and divide both values by that. The GCD is the highest number that evenly divides both numbers. So the GCD for 6 and 10 is 2, the GCD for 44 and 99 is 11.
For example, a 1024x768 monitor has a GCD of 256. When you divide bot...
