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How do I write the 'cd' command in a makefile?
...
It is actually executing the command, changing the directory to some_directory, however, this is performed in a sub-process shell, and affects neither make nor the shell you're working from.
If you're looking to perform more tasks wit...
How to deep copy a list?
... don't make a deep copy using list() (Both list(...) and testList[:] are shallow copies).
You use copy.deepcopy(...) for deep copying a list.
deepcopy(x, memo=None, _nil=[])
Deep copy operation on arbitrary Python objects.
See the following snippet -
>>> a = [[1, 2, 3], [4, 5, 6]]...
#ifdef replacement in the Swift language
... After i set the custom flag -DLOCAL, on my #if LOCAl #else #endif, it falls into the #else section. I duplicated the original target AppTarget and rename it to AppTargetLocal & set its custom flag.
– Perwyl Liu
Jul 20 '16 at 6:48
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Simulate CREATE DATABASE IF NOT EXISTS for PostgreSQL?
...an work around it from within psql by executing the DDL statement conditionally:
SELECT 'CREATE DATABASE mydb'
WHERE NOT EXISTS (SELECT FROM pg_database WHERE datname = 'mydb')\gexec
The manual:
\gexec
Sends the current query buffer to the server, then treats each column of each row of the query's...
Does IMDB provide an API? [closed]
...lo.json (alternate)
Format: JSON-P
Caveat: It's in JSON-P format, and the callback parameter can not customised. To use it cross-domain you'll have to use the function name they choose (which is in the imdb${searchphrase} format). Alternatively, one could strip or replace the padding via a local pro...
What does character set and collation mean exactly?
...a symbol, the number 0 is the
encoding for 'A', and the combination
of all four letters and their
encodings is a character set.
Now, suppose that we want to compare
two string values, 'A' and 'B'. The
simplest way to do this is to look at
the encodings: 0 for 'A' and 1 for
'B'. Be...
Adding days to a date in Python
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The previous answers are correct but it's generally a better practice to do:
import datetime
Then you'll have, using datetime.timedelta:
date_1 = datetime.datetime.strptime(start_date, "%m/%d/%y")
end_date = date_1 + datetime.timedelta(days=10)
...
How to sort a list in Scala by two fields?
... @SachinK: You could implement customOrdering as Ordering[Row] manually or using Ordering.by like this: val customOrdering = Ordering.by((r: Row) => (r.lastName, r.firstName))( Ordering.Tuple2(Ordering.String.reverse, Ordering.String) )`
– senia
Jun ...
Outputting data from unit test in python
... %r", self.that )
# etc.
self.assertEquals( 3.14, pi )
if __name__ == "__main__":
logging.basicConfig( stream=sys.stderr )
logging.getLogger( "SomeTest.testSomething" ).setLevel( logging.DEBUG )
unittest.main()
That allows us to turn on debugging for specific tests whi...
What do the python file extensions, .pyc .pyd .pyo stand for?
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.py: This is normally the input source code that you've written.
.pyc: This is the compiled bytecode. If you import a module, python will build a *.pyc file that contains the bytecode to make importing it again later easier (and faster).
.pyo...