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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...
How to compare type of an object in Python?
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isinstance works:
if isinstance(obj, MyClass): do_foo(obj)
but, keep in mind: if it looks like a duck, and if it sounds like a duck, it is a duck.
EDIT: For the None type, you can simply do:
if obj is None: obj = MyClass()
...
Python argparse mutual exclusive group
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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...
Easy way to write contents of a Java InputStream to an OutputStream
...this input stream and writes the bytes to the
given output stream in the order that they are read. On return, this
input stream will be at end of stream. This method does not close
either stream.
This method may block indefinitely reading from the
input stream, or writing to the output...
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...
Why is SELECT * considered harmful?
...code saves more time and effort in the long run.
If code depends on column order, SELECT * will hide an error waiting to happen if a table had its column order changed.
Even if you need every column at the time the query is written, that might not be the case in the future
the usage complicates pro...
How to set a selected option of a dropdown list control using angular JS
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I have a controler file named order.js, thus the html name the same order.html where the control is. Should I set the selectedVariant there or directly on the control?
– themhz
Jul 31 '13 at 11:40
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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?
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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 ...
IE7 Z-Index Layering Issues
...ou explicitly define how things overlap, even without z-index the layering order is well defined. Finally, IE6 has an additional bug that causes selectboxes and iframes to float on top of everything else.
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