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Is it possible to implement a Python for range loop without an iterator variable?
...munity wiki
7 revs, 3 users 87%Unknown
4
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List goals/targets in GNU make that contain variables in their definition
...vial makefile, dummy.mk, with these contents:
__all_targets__: ; #no-op
Now invoke make as make -p -f Makefile -f dummy.mk __all_targets__. On any substantial build, the difference in the amount of output generated by make is significant. For example:
$ gmake -pn | wc
138985 2632330 69612711
...
Why is __init__() always called after __new__()?
...it__ takes self as parameter. Until you create instance there is no self.
Now, I gather, that you're trying to implement singleton pattern in Python. There are a few ways to do that.
Also, as of Python 2.6, you can use class decorators.
def singleton(cls):
instances = {}
def getinstance(...
How to solve Operator '!=' cannot be applied to operands of type 'T' and 'T' [duplicate]
...os: Yeah I wonder how many people are using the wrong method in their code now...
– user541686
Oct 21 '13 at 21:14
...
Java: Date from unix timestamp
...ent the
specified number of milliseconds since
the standard base time known as "the
epoch", namely January 1, 1970,
00:00:00 GMT.
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Compare object instances for equality by their attributes
...lemented
return self.foo == other.foo and self.bar == other.bar
Now it outputs:
>>> x == y
True
Note that implementing __eq__ will automatically make instances of your class unhashable, which means they can't be stored in sets and dicts. If you're not modelling an immutable ty...
Elegant way to invert a map in Scala
... different keys associated with same values. So, if you are interested in knowing all the keys, here's the code:
scala> val m = Map(1 -> "a", 2 -> "b", 4 -> "b")
scala> m.groupBy(_._2).mapValues(_.keys)
res0: Map[String,Iterable[Int]] = Map(b -> Set(2, 4), a -> Set(1))
...
Why won't my PHP app send a 404 error?
...along whatever PHP gave me
In addition to providing a 404 header, PHP is now responsible for outputting the actual 404 page.
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How to set a Django model field's default value to a function call / callable (e.g., a date relative
...datetime, timedelta
class MyModel(models.Model):
# default to 1 day from now
my_date = models.DateTimeField(default=datetime.now() + timedelta(days=1))
This last line is not defining a function; it is invoking a function to create a field in the class.
PRE Django 1.7
Django lets you pass a ...
Generic deep diff between two objects
...d to format diff object in arbitrary way based on passed primitive values (now this job is done by "compareValues" method).
var deepDiffMapper = function () {
return {
VALUE_CREATED: 'created',
VALUE_UPDATED: 'updated',
VALUE_DELETED: 'deleted',
VALUE_UNCHANGED: 'unchanged',
...