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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...
how to emulate “insert ignore” and “on duplicate key update” (sql merge) with postgresql?
...gsql-control-structures.html, example 40-2 right at the bottom.
That's usually the easiest way. You can do some magic with rules, but it's likely going to be a lot messier. I'd recommend the wrap-in-function approach over that any day.
This works for single row, or few row, values. If you're deali...
Can I have onScrollListener for a ScrollView?
...
Every instance of View calls getViewTreeObserver(). Now when holding an instance of ViewTreeObserver, you can add an OnScrollChangedListener() to it using the method addOnScrollChangedListener().
You can see more information about this class here.
...
List of lists changes reflected across sublists unexpectedly
...
When you write [x]*3 you get, essentially, the list [x, x, x]. That is, a list with 3 references to the same x. When you then modify this single x it is visible via all three references to it:
x = [1] * 4
l = [x] * 3
print(f"id(x): {id(x)}")
# id(x): 1405608979...
WatiN or Selenium? [closed]
.... It will be a major upgrade to the current CTP 2.0 versions and will basically give you the same functionality to automate FireFox and IE as version 1.3.0 offers for automating IE.
So no concerns there.
Hope this helps in making your choice
Jeroen van Menen
Lead dev WatiN
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Are there any disadvantages to always using nvarchar(MAX)?
In SQL Server 2005, are there any disadvantages to making all character fields nvarchar(MAX) rather than specifying a length explicitly, e.g. nvarchar(255)? (Apart from the obvious one that you aren't able to limit the field length at the database level)
...
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: ...
VIM Replace word with contents of paste buffer?
... the one that'd get overwritten by the change command.)
Registers are generally specified by typing " then the name (single character) of the register, like "ay then "ap to yank into register a, then put the contents of register a. Same goes for a change command. In this case, if you don't want the ...
Python requests - print entire http request (raw)?
...ests.post(...) (or requests.get or requests.put, etc) methods, you can actually get the PreparedResponse through response.request. It can save the work of manually manipulating requests.Request and requests.Session, if you don't need to access the raw http data before you receive a response.
...
Generate a heatmap in MatPlotLib using a scatter data set
...50 heatmap. If you want, say, 512x384, you can put bins=(512, 384) in the call to histogram2d.
Example:
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