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What's the difference between ES6 Map and WeakMap?
...e: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/WeakMap):
Keys of WeakMaps are of the type Object only. Primitive data types as
keys are not allowed (e.g. a Symbol can't be a WeakMap key).
Nor can a string, number, or boolean be used as a WeakMap key. A M...
MongoDB with redis
...oDB does not have yet an expiration mechanism. Capped collections cannot really be used to implement a real TTL. Redis has a TTL-based expiration mechanism, making it convenient to store volatile data. For instance, user sessions are commonly stored in Redis, while user data will be stored and index...
How do I run a single test with Nose in Pylons
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nosetests appname.tests.functional.test_controller should work, where the file is named test_controller.py.
To run a specific test class and method use a path of the form module.path:ClassNameInFile.method_name, that is, with a colon separating the module/file pa...
not None test in Python [duplicate]
...r of the latter two, since val could potentially be of a type that defines __eq__() to return true when passed None.
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Get the first element of each tuple in a list in Python [duplicate]
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Use a list comprehension:
res_list = [x[0] for x in rows]
Below is a demonstration:
>>> rows = [(1, 2), (3, 4), (5, 6)]
>>> [x[0] for x in rows]
[1, 3, 5]
>>>
Alternately, you could use unpacking instead of x[0]:
res_li...
Samples of Scala and Java code where Scala code looks simpler/has fewer lines?
I need some code samples (and I also really curious about them) of Scala and Java code which show that Scala code is more simple and concise then code written in Java (of course both samples should solve the same problem).
...
How to use transactions with dapper.net?
...icitly roll back on error or does System.Transactions handle that automatically?
– Norbert Norbertson
Oct 3 '17 at 12:30
6
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Get keys from HashMap in Java
...HashMap contains more than one key. You can use keySet() to get the set of all keys.
team1.put("foo", 1);
team1.put("bar", 2);
will store 1 with key "foo" and 2 with key "bar". To iterate over all the keys:
for ( String key : team1.keySet() ) {
System.out.println( key );
}
will print "foo"...
Python: Using .format() on a Unicode-escaped string
...gt; print s
≥
>>> print "{0}".format(s)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
UnicodeEncodeError: 'ascii' codec can't encode character u'\u2265' in position 0: ordinal not in range(128)
>>> print u"{0}".format(s)
≥
>>>
...
Multiple inputs with same name through POST in php
... post and then access them from PHP? The idea is this: I have a form that allows the entry of an indefinite number of physical addresses along with other information. If I simply gave each of those fields the same name across several entries and submitted that data through post, would PHP be able ...