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Transactions in .net
...and doesn't allow cross-db work. An example (formatted for space):
using (IDbTransaction tran = conn.BeginTransaction()) {
try {
// your code
tran.Commit();
} catch {
tran.Rollback();
throw;
}
}
Not too messy, but limited to our connection "conn". If w...
Do declared properties require a corresponding instance variable?
...ally declare an instance variable between the braces, or via @property outside the braces, or both. Either way, they become attributes of the class. The difference is that if you declare @property, then you can implement using @synthesize, which auto-codes your getter/setter for you. The auto-coder ...
Groovy: what's the purpose of “def” in “def x = 0”?
... }
}
bar()
prints "error caught"
The "y" variable isn't in scope inside the function. "x" is in scope as groovy will check the bindings of the current script for the variable. As I said earlier, this is simply syntactic sugar to make quick and dirty scripts quicker to type out (often one li...
What is the Invariant Culture?
...ll always work because you serialized with the same culture << this didn't make sense to me, I think I misunderstood something. If using CultureInfo.InvariantCulture works because you serialized with the same culture....then isn't it the same as using CultureInfo.CurrentCulture?
...
“Debug only” code that should run only when “turned on”
....
#if DEBUG
private /*static*/ bool s_bDoDebugOnlyCode = false;
#endif
void foo()
{
// ...
#if DEBUG
if (s_bDoDebugOnlyCode)
{
// Code here gets executed only when compiled with the DEBUG constant,
// and when the person debugging manually sets the bool above to true.
...
Do I set properties to nil in dealloc when using ARC?
...hat it shouldn't touch in dealloc (e.g. if your class, or a subclass, overrides the setter). Similarly it may trigger KVO notifications. Releasing the ivar instead avoids these undesired behaviors.
In ARC, the system automatically releases any ivars for you, so if that's all you're doing you don't ...
Control the size of points in an R scatterplot?
... to be too small, but pch=19 to be too fat. Is there something in the middle or some way to scale the dots down somehow?
...
gunicorn autoreload on source change
... I don't believe there is a --reload option built into gunicorn. Where did you find this? Their docs say to reload the config, send a HUP (killall -HUP procname will work fine) to have new workers started and old ones gracefully shut down.
– sofly
Sep 24 '14...
Why does running the Flask dev server run itself twice?
...
Ah ok. Thanks for the explanation! So its considered normal behaviour? At least good that nothing's wrong with my code.. :)
– kramer65
Aug 26 '14 at 11:06
...
Django: How to completely uninstall a Django app?
...y_app_name gets you get the SQL statements that should be executed to get rid of all traces of the app in your DB. You still need to copy and paste (or pipe) those statements into your SQL client. For Django 1.7 and up, use ./manage.py migrate my_app_name zero (see the migrate docs), which runs the ...