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Why can't I use a list as a dict key in python?
...le, it'll work correctly with classes that have a custom comparison method __eq__. But if you convert them to strings, everything is compared by its string representation.
– Aran-Fey
May 20 '18 at 12:50
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Elegant way to invert a map in Scala
...
Assuming values are unique, this works:
(Map() ++ origMap.map(_.swap))
On Scala 2.8, however, it's easier:
origMap.map(_.swap)
Being able to do that is part of the reason why Scala 2.8 has a new collection library.
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How to convert an image to base64 encoding?
...hould be:
$path = 'myfolder/myimage.png';
$type = pathinfo($path, PATHINFO_EXTENSION);
$data = file_get_contents($path);
$base64 = 'data:image/' . $type . ';base64,' . base64_encode($data);
share
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How do I spool to a CSV formatted file using SQLPLUS?
... numbers (avoid scientific notation on IDs)
spool myfile.csv
select table_name, tablespace_name
from all_tables
where owner = 'SYS'
and tablespace_name is not null;
Output will be like:
TABLE_PRIVILEGE_MAP ,SYSTEM
SYSTEM_PRIVILEGE_MAP ,S...
What is the fastest/most efficient way to find the highest set bit (msb) in an integer in C?
...
GCC has:
-- Built-in Function: int __builtin_clz (unsigned int x)
Returns the number of leading 0-bits in X, starting at the most
significant bit position. If X is 0, the result is undefined.
-- Built-in Function: int __builtin_clzl (unsigned long...
Can I serve multiple clients using just Flask app.run() as standalone?
...onal keyword arguments (**options) that it forwards to werkzeug.serving.run_simple - two of those arguments are threaded (a boolean) and processes (which you can set to a number greater than one to have werkzeug spawn more than one process to handle requests).
threaded defaults to True as of Flask ...
What does #defining WIN32_LEAN_AND_MEAN exclude exactly?
I found the explanation defining WIN32_LEAN_AND_MEAN "reduces the size of the Win32 header files by excluding some of the less frequently used APIs". Somewhere else I read that it speeds up the build process.
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Flatten nested dictionaries, compressing keys
...ng the dictionary at final step.
import collections
def flatten(d, parent_key='', sep='_'):
items = []
for k, v in d.items():
new_key = parent_key + sep + k if parent_key else k
if isinstance(v, collections.MutableMapping):
items.extend(flatten(v, new_key, sep=s...
How to download a file from a URL in C#?
...ethod also supports local files as 1st parameter
– oo_dev
Aug 22 '17 at 8:35
The MSDN doc did mention to use HttpClien...
How to darken a background using CSS?
... image */
url(http://fc02.deviantart.net/fs71/i/2011/274/6/f/ocean__sky__stars__and_you_by_muddymelly-d4bg1ub.png);
}
Reference: linear-gradient() - CSS | MDN
UPDATE: Not all browsers support RGBa, so you should have a 'fallback color'. This color will be most likely be solid (...