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What does {0} mean when initializing an object?
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What's happening here is called aggregate initialization. Here is the (abbreviated) definition of an aggregate from section 8.5.1 of the ISO spec:
An aggregate is an array or a class with no user-declared constructors, no private or protected non...
Equivalent of strace -feopen < command > on mac os X
...day, sudo dtruss doesn't work for me. It's as if Python is not executed at all!
– Dima Tisnek
Jul 18 '13 at 14:27
2
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In STL maps, is it better to use map::insert than []?
...els natural and is clear to read whereas he preferred map.insert(std::make_pair(key, value)) .
13 Answers
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Python: Get the first character of the first string in a list?
...ist char for the first one string(item):
myList[0][0]
>>> b
If all first chars:
[x[0] for x in myList]
>>> ['b', 's', 't']
If you have a text:
text = 'base sample test'
text.split()[0][0]
>>> b
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Center image horizontally within a div
...age are not working I thought I would ask. How can I center align (horizontally) an image inside its container div?
21 Answ...
Count all occurrences of a string in lots of files with grep
...a bunch of log files. I need to find out how many times a string occurs in all files.
15 Answers
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Some built-in to pad a list in python
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a += [''] * (N - len(a))
or if you don't want to change a in place
new_a = a + [''] * (N - len(a))
you can always create a subclass of list and call the method whatever you please
class MyList(list):
def ljust(self, n, fillvalue=''):
return self + [fillvalue] * (n - len(self))
a...
How can I use if/else in a dictionary comprehension?
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@Marcin's answer covers it all, but just in case someone wants to see an actual example, I add two below:
Let's say you have the following dictionary of sets
d = {'key1': {'a', 'b', 'c'}, 'key2': {'foo', 'bar'}, 'key3': {'so', 'sad'}}
and you want ...
Best way to work with dates in Android SQLite [closed]
...at, the default if you use datetime('now') (yyyy-MM-dd HH:mm:ss) will then allow sorting by the date column.
Retrieving dates as strings from SQLite you can then format/convert them as required into local regionalised formats using the Calendar or the android.text.format.DateUtils.formatDateTime me...
What does the “===” operator do in Ruby? [duplicate]
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Just like with every other method in Ruby (or actually pretty much any object-oriented language),
a === b
means whatever the author of a's class wants it to mean.
However, if you don't want to confuse the heck out of your colleagues, the convention is that === is the cas...