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Why is Scala's immutable Set not covariant in its type?
... worth losing the use of that covariant type?
– oxbow_lakes
Mar 24 '09 at 22:00
23
The type signa...
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]....
How to convert a Drawable to a Bitmap?
....getResources(),
R.drawable.icon_resource);
Here a version where the image gets downloaded.
String name = c.getString(str_url);
URL url_value = new URL(name);
ImageView profile = (ImageView)v.findViewById(R.id.vdo_icon);
if (profile != null) {
Bitmap...
Parameterize an SQL IN clause
...fun, this time, we'll use $ as the escape character.
select ...
where '|p_%t!r|'
like '%|' + REPLACE(REPLACE(REPLACE( 'p_%t!r' ,'$','$$'),'%','$%'),'_','$_') + '|%' escape '$'
I prefer this approach to escaping because it works in Oracle and MySQL as well as SQL Server. (I usually use the \ b...
Reactjs convert html string to jsx
...se the dangerouslySetInnerHTML property:
<td dangerouslySetInnerHTML={{__html: this.state.actions}} />
React forces this intentionally-cumbersome syntax so that you don't accidentally render text as HTML and introduce XSS bugs.
...
Find out how much memory is being used by an object in Python [duplicate]
...
Try this:
sys.getsizeof(object)
getsizeof() calls the object’s __sizeof__ method and adds an additional garbage collector overhead if the object is managed by the garbage collector.
A recursive recipe
share
...
How to access app.config in a blueprint?
...horisation.py which in a package api. I am initializing the blueprint in __init__.py which is used in authorisation.py .
...
bool to int conversion
... 1, 4>5 would evaluate to 0.
EDIT: Jens in the comment said, C99 has _Bool type. bool is a macro defined in stdbool.h header file. true and false are also macro defined in stdbool.h.
§7.16 from C99 says,
The macro bool expands to _Bool.
[..] true which expands to the integer constan...
Combine --user with --prefix error with setup.py install
...me workaround:
pip install --user --install-option="--prefix=" <package_name>
or
python setup.py install --user --prefix=
Note that there is no text (not even whitespace) after the =.
Do not forget the --user flag.
Installing multiple packages:
Create ~/.pydistutils.cfg (or equivalent...
How to define hash tables in Bash?
...are the answer by introducing the concepts:
First, indirection.
$ animals_moo=cow; sound=moo; i="animals_$sound"; echo "${!i}"
cow
Secondly, declare:
$ sound=moo; animal=cow; declare "animals_$sound=$animal"; echo "$animals_moo"
cow
Bring them together:
# Set a value:
declare "array_$index=$...