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How do I check if a variable exists?
...have nested functions, variables in outer scopes. If you want to check for all of them, you're probably best off triggering NameError after all.
– Petr Viktorin
Jun 10 '14 at 20:18
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Difference between -pthread and -lpthread while compiling
...that get defined when the -pthread option gets used on the GCC package installed on my Ubuntu machine:
$ gcc -pthread -E -dM test.c > dm.pthread.txt
$ gcc -E -dM test.c > dm.nopthread.txt
$ diff dm.pthread.txt dm.nopthread.txt
152d151
< #define _REENTRANT 1
208d206
< #define _...
How do I create a link using javascript?
....attr('href',desiredLink);
a.text(desiredText);
$('body').append(a);
In all the above examples you can append the anchor to any element, not just to the 'body', and desiredLink is a variable that holds the address that your anchor element points to, and desiredText is a variable that holds the te...
Passing Data between View Controllers
...h it onto nav stack.
ViewControllerB *viewControllerB = [[ViewControllerB alloc] initWithNib:@"ViewControllerB" bundle:nil];
viewControllerB.isSomethingEnabled = YES;
[self pushViewController:viewControllerB animated:YES];
This will set isSomethingEnabled in ViewControllerB to BOOL value YES.
P...
Difference between Ctrl+Shift+F and Ctrl+I in Eclipse
... just format tabs/whitespaces in code and pressing CTRL + SHIFT + F format all code that is format tabs/whitespaces and also divide code lines in a way that it is visible without horizontal scroll.
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The conversion of a datetime2 data type to a datetime data type resulted in an out-of-range value
...orm (headline, story, and image). ApplyPropertyChanges applies changes to all properties of the object, including your uninitialized DateTime, which is set to 0001-01-01, which is outside of the range of SQL Server's DATETIME.
Rather than using ApplyPropertyChanges, I'd suggest retrieving the obje...
How can I pass parameters to a partial view in mvc 4
...l with just the partial name:
@Html.Partial("_SomePartial")
It will actually pass your model as an implicit parameter, the same as if you were to call:
@Html.Partial("_SomePartial", Model)
Now, in order for your partial to actually be able to use this, though, it too needs to have a defined mo...
How to exclude certain directories/files from git grep search
...va files from under your current directory).
There's a good reference for all the "magic words" allowed in a pathspec at git-scm.com (or just git help glossary). For some reason, the docs at kernel.org are really out of date even though they often come up first in google searches.
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How can you customize the numbers in an ordered list?
...ilar to that given in other answers. But instead of using content: counter(foo), we use content: attr(seq).
Demo in CodePen with more styling
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Difference between exit() and sys.exit() in Python
...raising SystemExit. sys.exit does so in sysmodule.c:
static PyObject *
sys_exit(PyObject *self, PyObject *args)
{
PyObject *exit_code = 0;
if (!PyArg_UnpackTuple(args, "exit", 0, 1, &exit_code))
return NULL;
/* Raise SystemExit so callers may catch it or clean up. */
PyE...