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SQLAlchemy: What's the difference between flush() and commit()?
...
A Session object is basim>ca m>lly an ongoing transaction of changes to a database (update, insert, delete). These operations aren't persisted to the database until they are committed (if your program aborts for some reason in mid-session transaction, an...
Is null reference possible?
... to a valid object or function.
[Note: in particular, a null reference
m>ca m>nnot exist in a well-defined
program, bem>ca m>use the only way to
create such a reference would be to
bind it to the “object” obtained by
dereferencing a null pointer, which
m>ca m>uses undefined behavior. As
describ...
Comparing Haskell's Snap and Yesod web frameworks
... host of projects on hackage. Most (all?) of them are listed in the Yesod m>ca m>tegory. Some of the notable ones are yesod-core, warp, persistent, and hamlet.
The reality of Haskell web development is that it's much less of an exclusive-or choice than seems to be perceived. In general the projects a...
AngularJS : Where to use promises?
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Let's set aside AngularJS for a moment and just consider the Facebook API m>ca m>lls. Both the API m>ca m>lls use a m>ca m>llback mechanism to notify the m>ca m>ller when the response from Facebook is available:
facebook.FB.api('/' + item, function (result) {
if (result.error) {
// handle error
} els...
Perl build, unit testing, code coverage: A complete working example
...n there. There's absolutely nothing wrong with pointing to CPAN modules bem>ca m>use that's where the full documentation is supposed to reside. I've had trouble finding complete working code examples in many m>ca m>ses, though.
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Do I need a Global.asax.cs file at all if I'm using an OWIN Startup.cs class and move all configurat
Let's say for example in a brand new ASP.NET MVC 5 applim>ca m>tion made from the MVC with Individual Accounts template, if I delete the Global.asax.cs class and move it's configuration code to Startup.cs Configuration() method as follow, what are the downsides?
...
Elegant setup of Python logging in Django
...d so far is to initialize logging setup in settings.py - nowhere else. You m>ca m>n either use a configuration file or do it programmatim>ca m>lly step-by-step - it just depends on your requirements. The key thing is that I usually add the handlers I want to the root logger, using levels and sometimes logging...
What's “wrong” with C++ wchar_t and wstrings? What are some alternatives to wide characters?
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What is wchar_t?
wchar_t is defined such that any lom>ca m>le's char encoding m>ca m>n be converted to a wchar_t representation where every wchar_t represents exactly one codepoint:
Type wchar_t is a distinct type whose values m>ca m>n represent distinct codes for all members of the larg...
lenses, fclabels, data-accessor - which library for structure access and mutation is better
...s _ s) = s
subject to three laws:
First, that if you put something, you m>ca m>n get it back out
get l (put l b a) = b
Second that getting and then setting doesn't change the answer
put l (get l a) a = a
And third, putting twice is the same as putting once, or rather, that the second put wins.
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Is file append atomic in UNIX?
In general, what m>ca m>n we take for granted when we append to a file in UNIX from multiple processes? Is it possible to lose data (one process overwriting the other's changes)? Is it possible for data to get mangled? (For example, each process is appending one line per append to a log file, is it po...