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C-like structures in Python
...ou might run into later as well. Your fragment above would be written as:
from collections import namedtuple
MyStruct = namedtuple("MyStruct", "field1 field2 field3")
The newly created type can be used like this:
m = MyStruct("foo", "bar", "baz")
You can also use named arguments:
m = MyStruct...
Regular Expression to get a string between parentheses in Javascript
...Each(x => {
const matches = [...x.matchAll(rx)];
console.log( Array.from(matches, m => m[0]) ); // All full match values
console.log( Array.from(matches, m => m[1]) ); // All Group 1 values
});
Legacy JavaScript code demo (ES5 compliant):
var strs = ["I expect five hundred d...
isset() and empty() - what to use
...y array)
var $var; (a variable declared, but without a value in a class)
From http://php.net/manual/en/function.empty.php
As mentioned in the comments the lack of warning is also important with empty()
PHP Manual says
empty() is the opposite of (boolean) var, except that no warning is
ge...
Does Python's time.time() return the local or UTC timestamp?
...563265.81
>>> import datetime
>>> st = datetime.datetime.fromtimestamp(ts).strftime('%Y-%m-%d %H:%M:%S')
>>> print st
2012-12-15 01:21:05
>>>
The ts variable is the time returned in seconds. I then converted it to a string using the datetime library making it a...
Why is processing a sorted array faster than processing an unsorted array?
...less.
Further reading: "Branch predictor" article on Wikipedia.
As hinted from above, the culprit is this if-statement:
if (data[c] >= 128)
sum += data[c];
Notice that the data is evenly distributed between 0 and 255. When the data is sorted, roughly the first half of the iterations will no...
What kind of Garbage Collection does Go use?
...least have predictable and controllable heap growth behavior.
(Photo from GopherCon 2015 presentation "Go GC: Solving the Latency Problem in Go 1.5")
The sole tuning knob for the STW collector was “GOGC”, the relative heap growth between collections. The default setting, 100%, triggered g...
How do I space out the child elements of a StackPanel?
...emsControl bound to a changing collection. It assumes the items are static from the moment the parent's Load event fires.
– Drew Noakes
Oct 9 '17 at 14:59
...
Maven: Non-resolvable parent POM
...anks I tried it for a while to solve the problem. I took the relative path from ../pom.xml to ../<parent folder>/pom.xml.
– Mario Kurzweil
Feb 4 '17 at 19:36
...
Save bitmap to location
I am working on a function to download an image from a web server, display it on the screen, and if the user wishes to keep the image, save it on the SD card in a certain folder. Is there an easy way to take a bitmap and just save it to the SD card in a folder of my choice?
...
What is JSONP, and why was it created?
...gs, the ones you usually use to load js files, in order for js to get data from another domain. Sounds weird?
Thing is - turns out script tags can be used in a fashion similar to XMLHttpRequest! Check this out:
script = document.createElement('script');
script.type = 'text/javascript';
script.src ...
