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What's the idiomatic syntax for prepending to a short python list?
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The s.insert(0, x) form is the most common.
Whenever you see it though, it may be time to consider using a collections.deque instead of a list.
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In-memory size of a Python structure
...gt;>> import decimal
>>>
>>> d = {
... "int": 0,
... "float": 0.0,
... "dict": dict(),
... "set": set(),
... "tuple": tuple(),
... "list": list(),
... "str": "a",
... "unicode": u"a",
... "decimal": decimal.Decimal(0),
... "object": ob...
Disable/turn off inherited CSS3 transitions
..." class="transition">Content</a>
...and CSS:
a {
color: #f90;
-webkit-transition:color 0.8s ease-in, background-color 0.1s ease-in ;
-moz-transition:color 0.8s ease-in, background-color 0.1s ease-in;
-o-transition:color 0.8s ease-in, background-color 0.1s ease-in;
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php is null or empty?
...LL) {...}
Note the ===.
When use ==, as you did, PHP treats NULL, false, 0, the empty string, and empty arrays as equal.
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Zooming MKMapView to fit annotation pins?
...MKMapView and have added a number of annotation pins to the map about a 5-10 kilometre area. When I run the application my map starts zoomed out to show the whole world, what is the best way to zoom the map so the pins fit the view?
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Is it possible to change only the alpha of a rgba background colour on hover?
... { display: block; position: relative; }
div { position: absolute; bottom: 0; background-color: rgba(var(--rgb), 0.8); }
a:hover div { background-color: rgba(var(--rgb), 1); }
To understand how this works, see How do I apply opacity to a CSS color variable?
If custom properties are not an option,...
Why is there no xrange function in Python3?
...pple 2.7.2 64-bit:
In [37]: %timeit collections.deque((x for x in xrange(10000000) if x%4 == 0), maxlen=0)
1 loops, best of 3: 1.05 s per loop
Now, python.org 3.3.0 64-bit:
In [83]: %timeit collections.deque((x for x in range(10000000) if x%4 == 0), maxlen=0)
1 loops, best of 3: 1.32 s per loop
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How to do version numbers? [closed]
...e "unstable watchout" on there. So how would you go about versioning? Is 1.0 stable? Should the build date be in the version number? Tell me what you guys think!
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Add unique constraint to combination of two columns
...g an exception (exceptions are expensive).
http://www.sqlperformance.com/2012/08/t-sql-queries/error-handling
http://www.mssqltips.com/sqlservertip/2632/checking-for-potential-constraint-violations-before-entering-sql-server-try-and-catch-logic/
If you want to prevent exceptions from bubbling up ...
How to go about formatting 1200 to 1.2k in java
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+100
Here is a solution that works for any long value and that I find quite readable (the core logic is done in the bottom three lines of ...