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Concurrent vs serial queues in GCD
...URL = URL(string: "https://upload.wikimedia.org/wikipedia/commons/0/07/Huge_ball_at_Vilnius_center.jpg")!
let _ = try! Data(contentsOf: imgURL)
print("\(i) completed downloading")
}
}
}
Task will run in different thread(other than main thread) when you use as...
Cost of len() function
...s, not C terms]: look up "len" in a dictionary and dispatch it to the built_in len function which will look up the object's __len__ method and call that ... all it has to do is return self.length
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Targeting only Firefox with CSS
...nger works as of Firefox 59, released March 2018: bugzilla.mozilla.org/show_bug.cgi?id=1035091
– Jordan Gray
Dec 17 '19 at 17:16
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show 8 mo...
Get an OutputStream into a String
....charset.Charset. A possible value is java.nio.charset.StandardCharsets.UTF_8.
The method toString() accepts only a String as a codepage parameter (stand Java 8).
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...
What breaking changes are introduced in C++11?
...bc"
const char *s = u8"def"; // Previously "abcdef", now "def"
#define _x "there"
"hello"_x // now a user-defined-string-literal. Previously, expanded _x .
New keywords: alignas, alignof, char16_t, char32_t, constexpr, decltype, noexcept, nullptr, static_assert, and thread_local
Ce...
MongoDB drop every database
...
Save this to drop_all_dbs.js:
var databases = db.getMongo().getDBNames()
for(var i in databases){
db = db.getMongo().getDB( databases[i] );
if(db.getName() == "admin" || db.getName() == "local"){
print("skipping db " + db.get...
Export database schema into SQL file
...leType as table (ObjectID int)
here the SP:
create PROCEDURE [dbo].[util_ScriptTable]
@DBName SYSNAME
,@schema sysname
,@TableName SYSNAME
,@IncludeConstraints BIT = 1
,@IncludeIndexes BIT = 1
,@NewTableSchema sysname
,@NewTableName SYSNAME = NULL
,@UseSystemData...
Configuring so that pip install can work from github
...oo would be:
foo # the installable package
├── foo
│ ├── __init__.py
│ └── bar.py
└── setup.py
And install from github like:
$ pip install git+ssh://git@github.com/myuser/foo.git
or
$ pip install git+https://github.com/myuser/foo.git@v123
or
$ pip install git+htt...
In Python, how does one catch warnings as if they were exceptions?
...):
warnings.warn("deprecated", DeprecationWarning)
with warnings.catch_warnings(record=True) as w:
# Cause all warnings to always be triggered.
warnings.simplefilter("always")
# Trigger a warning.
fxn()
# Verify some things
assert len(w) == 1
assert issubclass(w[-1]....
nonlocal keyword in Python 2.x
... @BobStein Sorry, I don't really understand what you mean. But by adding __slots__ = () and creating an object instead of using the class, e.g. context.z = 3 would raise an AttributeError. It is possible for all classes, unless they inherit from a class not defining slots.
– ...