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When to use lambda, when to use Proc.new?
...n statement:
In a lambda-created proc, the return statement returns only from the proc itself
In a Proc.new-created proc, the return statement is a little more surprising: it returns control not just from the proc, but also from the method enclosing the proc!
Here's lambda-created proc's return ...
How to get the current time as datetime
...ate()
let calendar = Calendar.current
let hour = calendar.component(.hour, from: date)
let minutes = calendar.component(.minute, from: date)
I do this:
let date = NSDate()
let calendar = NSCalendar.currentCalendar()
let components = calendar.components(.CalendarUnitHour | .CalendarUnitMinute, f...
How do I remove a property from a JavaScript object?
...e
The delete operator does not directly free memory, and it differs from simply assigning the value of null or undefined to a property, in that the property itself is removed from the object. Note that if the value of a deleted property was a reference type (an object), and another part of yo...
How to calculate an angle from three points? [closed]
...P132 - P232) / (2 *
P12 * P13))
where P12 is the length of the segment from P1 to P2, calculated by
sqrt((P1x -
P2x)2 +
(P1y -
P2y)2)
share
edited Aug 25 '16 at...
Git and Mercurial - Compare and Contrast
...g list, and even contribute a bit to Git (gitweb mainly). I know Mercurial from documentation and some from discussion on #revctrl IRC channel on FreeNode.
Thanks to all people on on #mercurial IRC channel who provided help about Mercurial for this writeup
Summary
Here it would be nice to have som...
How to write a Python module/package?
...
would that last one be: from HellowModule import hellomodule? Could that be hello in the module folder, so it would be from HelloModule import hello
– nycynik
Feb 22 '15 at 13:33
...
Iterator invalidation rules
...
C++17 (All references are from the final working draft of CPP17 - n4659)
Insertion
Sequence Containers
vector: The functions insert, emplace_back, emplace, push_back cause reallocation if the new size is greater than the old capacity. Reallocation ...
How does Access-Control-Allow-Origin header work?
...Cross-Origin Resource Sharing) header.
When Site A tries to fetch content from Site B, Site B can send an Access-Control-Allow-Origin response header to tell the browser that the content of this page is accessible to certain origins. (An origin is a domain, plus a scheme and port number.) By defa...
Detect & Record Audio in Python
...o Nick Fortescue's answer, here's a more complete example of how to record from the microphone and process the resulting data:
from sys import byteorder
from array import array
from struct import pack
import pyaudio
import wave
THRESHOLD = 500
CHUNK_SIZE = 1024
FORMAT = pyaudio.paInt16
RATE = 441...
Node.js throws “btoa is not defined” error
...eed to convert to Base64 you could do so using Buffer:
console.log(Buffer.from('Hello World!').toString('base64'));
Reverse (assuming the content you're decoding is a utf8 string):
console.log(Buffer.from(b64Encoded, 'base64').toString());
Note: prior to Node v4, use new Buffer rather than B...