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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(...
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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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
...
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))
...
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...
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',
...