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Autoreload of modules in IPython [duplicate]
Is there a way to have IPython automatically reload all changed code? Either before each line is executed in the shell or failing that when it is specifically requested to. I'm doing a lot of exploratory programming using IPython and SciPy and it's quite a pain to have to manually reload each module...
Get model's fields in Django
Given a Django model, I'm trying to list all of its fields. I've seen some examples of doing this using the _meta model attribute, but doesn't the underscore in front of meta indicate that the _meta attribute is a private attribute and shouldn't be accessed directly? ... Because, for example, the ...
How to read if a checkbox is checked in PHP?
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this is the really good form to do this in pure simple php. but have to note that the value of a checkbox is string on when it is activated an a inexisting value if it is checked.
– Elvis Technologies
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What does the Ellipsis object do?
While idly surfing the namespace I noticed an odd looking object called Ellipsis , it does not seem to be or do anything special, but it's a globally available builtin.
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In where shall I use isset() and !empty()
... it's not a good idea to use this operator for math in case "0" is accidentally a string. This can be dangerous. Instead, use basic >, < and == operators and convert variables using intval() or floatval().
– kaleazy
Feb 14 at 18:08
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C++ equivalent of java's instanceof
...nceof) you'd better ask yourself whether it's a necessary thing. It's generally a sign of poor design.
Typical workarounds is putting the special behaviour for the class you are checking for into a virtual function on the base class or perhaps introducing something like a visitor where you can int...
Adding a new value to an existing ENUM Type
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It's worth mentioning that this can all be done in a single transaction, so it's mostly safe to do it in a production database.
– David Leppik
Jul 8 '11 at 20:41
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Difference between Node object and Element object?
I am totally confused between Node object and Element object.
document.getElementById() returns Element object while document.getElementsByClassName()
returns NodeList object(Collection of Elements or Nodes?)
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How to make a variadic macro (variable number of arguments)
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The reason for ## before VA_ARGS is that it swallows the preceding comma in case the variable-argument list is empty, eg. FOO("a") expands to printf("a"). This is an extension of gcc (and vc++, maybe), C99 requires at least one argument to be present in place of the elli...
ARC and bridged cast
...__bridge_transfer? Otherwise it would seem that the moment CFRelease() is called the object is gone and points to nothing. Similarly, when you use __bridge_retain, does ARC reduce the op's retain count by 1? Else it seems that the object would never be properly released.
– Tony...