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Python None comparison: should I use “is” or ==?
...ject None, so when you do my_var is None, you're checking whether they actually are the same object (not just equivalent objects)
In other words, == is a check for equivalence (which is defined from object to object) whereas is checks for object identity:
lst = [1,2,3]
lst == lst[:] # This is Tr...
Find the files existing in one directory but not in the other [closed]
...rison is to use find with md5sum, then a diff.
Example:
Use find to list all the files in the directory then calculate the md5 hash for each file and pipe it to a file:
find /dir1/ -type f -exec md5sum {} \; > dir1.txt
Do the same procedure to the another directory:
find /dir2/ -type f -exe...
Avoid browser popup blockers
...m javascript that is not invoked by direct user action. That is, you can call window.open in response to a button click without getting hit by the popup blocker, but if you put the same code in a timer event it will be blocked. Depth of call chain is also a factor - some older browsers only look a...
Loop through all nested dictionary values?
I'm trying to loop through a dictionary and print out all key value pairs where the value is not a nested dictionary. If the value is a dictionary I want to go into it and print out its key value pairs...etc. Any help?
...
MongoDB Many-to-Many Association
... user document:
{name:"Joe"
,roles:["Admin","User","Engineer"]
}
To get all the Engineers, use:
db.things.find( { roles : "Engineer" } );
If you want to maintain the roles in separate documents then you can include the document's _id in the roles array instead of the name:
{name:"Joe"
,roles:...
Why is TypedReference behind the scenes? It's so fast and safe… almost magical!
...ecification, the constructs used to implement them under the hood (vararg calling convention, TypedReference type, arglist, refanytype, mkanyref, and refanyval instructions) are perfectly documented in the CLI Specification (ECMA-335) in the Vararg library.
Being defined in the Vararg Library makes ...
C# Float expression: strange behavior when casting the result float to int
...
First of all, I assume that you know that 6.2f * 10 is not exactly 62 due to floating point rounding (it's actually the value 61.99999809265137 when expressed as a double) and that your question is only about why two seemingly identic...
How to convert an array into an object using stdClass() [duplicate]
..., 'varsta' => 25)
);
If you want to see is this stdClass object just call this
print_r($clasa);
If you want to convert an array to object code will be
$arr = array('a'=>'apple','b'=>'ball');
$arr = (object) $arr;
You don't need to use stdClass. It will automatically converted to st...
Run an Application in GDB Until an Exception Occurs
... a C++ exception.
catch
The catching of a C++ exception.
exec
A call to exec. This is currently only available for HP-UX.
fork
A call to fork. This is currently only available for HP-UX.
vfork
A call to vfork. This is currently only available for HP-UX.
load or load libname
...
How do I specify different Layouts in the ASP.NET MVC 3 razor ViewStart file?
... One potential problem with LayoutInjecterAttribute: It is called before the controller's OnException method. So, if the controller provides a view result during exception handling, the layout won't be set.
– Jeff Sharp
Apr 21 '14 at 17:03
...