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Scala: List[Future] to Future[List] disregarding failed futures
...
def futureToFutureTry[T](f: Future[T]): Future[Try[T]] =
f.map(Success(_)).recover { case x => Failure(x)}
val listOfFutures = ...
val listOfFutureTrys = listOfFutures.map(futureToFutureTry(_))
Then use Future.sequence as before, to give you a Future[List[Try[T]]]
val futureListOfTrys = F...
Python argparse mutual exclusive group
...
add_mutually_exclusive_group doesn't make an entire group mutually exclusive. It makes options within the group mutually exclusive.
What you're looking for is subcommands. Instead of prog [ -a xxxx | [-b yyy -c zzz]], you'd hav...
sqlalchemy: how to join several tables by one query?
...integer primary keys for everything, but whatever):
class User(Base):
__tablename__ = 'users'
email = Column(String, primary_key=True)
name = Column(String)
class Document(Base):
__tablename__ = "documents"
name = Column(String, primary_key=True)
author_email = Column(Strin...
Get name of object or class
... use standard IIFE (for example with TypeScript)
var Zamboch;
(function (_Zamboch) {
(function (Web) {
(function (Common) {
var App = (function () {
function App() {
}
App.prototype.hello = function () {
co...
How to print a dictionary line by line in Python?
...
I do print(json.dumps(cars, indent=4, ensure_ascii=False)) because otherwise non-ASCII characters are unreadable.
– Boris
Apr 22 at 16:36
add a ...
How does cookie based authentication work?
...What does the browser need to do? What does the server need to do? In what order? How do we keep things secure?
3 Answers
...
How to write inline if statement for print?
... condition:
block
if expression (introduced in Python 2.5)
expression_if_true if condition else expression_if_false
And note, that both print a and b = a are statements. Only the a part is an expression. So if you write
print a if b else 0
it means
print (a if b else 0)
and similarly ...
NumPy array initialization (fill with identical values)
...Rolf Bartstra.)
a=np.empty(n); a.fill(5) is fastest.
In descending speed order:
%timeit a=np.empty(1e4); a.fill(5)
100000 loops, best of 3: 5.85 us per loop
%timeit a=np.empty(1e4); a[:]=5
100000 loops, best of 3: 7.15 us per loop
%timeit a=np.ones(1e4)*5
10000 loops, best of 3: 22.9 us per lo...
What's the difference between using CGFloat and float?
...undation source code, in CoreGraphics' CGBase.h:
/* Definition of `CGFLOAT_TYPE', `CGFLOAT_IS_DOUBLE', `CGFLOAT_MIN', and
`CGFLOAT_MAX'. */
#if defined(__LP64__) && __LP64__
# define CGFLOAT_TYPE double
# define CGFLOAT_IS_DOUBLE 1
# define CGFLOAT_MIN DBL_MIN
# define CGFLOAT_MAX DBL_M...
Query to list number of records in each table in a database
...id <= 1
GROUP BY
t.NAME, i.object_id, i.index_id, i.name, p.[Rows]
ORDER BY
object_name(i.object_id)
In my opinion, it's easier to handle than the sp_msforeachtable output.
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