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Javascript - How to detect if document has loaded (IE 7/Firefox 3)
I want to call a function after a document loads, but the document may or may not have finished loading yet. If it did load, then I can just call the function. If it did NOT load, then I can attach an event listener. I can't add an eventlistener after onload has already fired since it won't get cal...
open read and close a file in 1 line of code
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You don't really have to close it - Python will do it automatically either during garbage collection or at program exit. But as @delnan noted, it's better practice to explicitly close it for various reasons.
So, what you can do to keep ...
How to get object length [duplicate]
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This is actually worse than using a simple loop and counter because of the added overhead of the callback function.
– nullability
Feb 19 '13 at 17:35
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Access an arbitrary element in a dictionary in Python
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for a non-destructive popitem you can make a (shallow) copy: key, value = dict(d).popitem()
– Pelle
Jan 31 '18 at 10:35
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MongoDB/NoSQL: Keeping Document Change History
... changes to one or more specific entities in a database. I've heard this called row versioning, a log table or a history table (I'm sure there are other names for it). There are a number of ways to approach it in an RDBMS--you can write all changes from all source tables to a single table (more of...
Align contents inside a div
...d to make sure Standards Mode is on by using a suitable DOCTYPE.
If you really need to support IE5/Quirks Mode, which these days you shouldn't really, it is possible to combine the two different approaches to centering:
<div style="text-align: center">
<div style="width: 50%; margin: ...
How to get string objects instead of Unicode from JSON?
...unicode strings, then recurses through the entire decoded value to convert all strings to byte strings. This has a couple of undesirable effects:
A copy of the entire decoded structure gets created in memory
If your JSON object is really deeply nested (500 levels or more) then you'll hit Python's ...
Getting Java version at runtime
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Wow, that kind of blew my mind. Though in my case, all I wanted was the first two parts of the version so: Runtime.class.getPackage().getSpecificationVersion()
– Wesley Hartford
Dec 10 '14 at 21:44
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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:...
Adding a cross-reference to a subheading or anchor in another page
... because it works across files, when section headings are changed, and for all builders that support cross-references.
RST, in General
The tools that convert RST files to HTML do not necessarily have a notion of collection. This is the case for instance if you rely on github to convert RST files ...