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Why does 'continue' behave like 'break' in a Foreach-Object?
..., it simulates the continue in a loop.
1..100 | ForEach-Object {
if ($_ % 7 -ne 0 ) { return }
Write-Host "$($_) is a multiple of 7"
}
There is a gotcha to be kept in mind when refactoring. Sometimes one wants to convert a foreach statement block into a pipeline with a ForEach-Object cmdl...
How to detect if a function is called as constructor?
... // except in in EcmaScript 5 strict mode.
&& !this.__previouslyConstructedByX) {
isConstructor = true;
this.__previouslyConstructedByX = true;
}
alert(isConstructor);
}
Obviously this is not ideal, since you now have an extra useless property on ever...
滚动控制使用指导 · App Inventor 2 中文网
...动条布局（高度设为 300 像素），在里面放一个标签 标签_记录（勾选「HTML格式」）；
布局下方放一个文本输入框、两个按钮（按钮_发送、按钮_回顶部）和一个滚动控制；
搭下面的代码块：每发一条消息追加到记录末尾并...
What is the purpose of double curly braces in React's JSX syntax?
... an object literal inlined in the prop value. It's the same as
var obj = {__html: rawMarkup};
<span dangerouslySetInnerHTML={obj} />
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fo...
What algorithm does Readability use for extracting text from URLs?
...spaper';
readSize = 'size-medium';
readMargin = 'margin-wide';
_readability_script = document.createElement('script');
_readability_script.type = 'text/javascript';
_readability_script.src = 'http://lab.arc90.com/experiments/readability/js/readability.js?x=' + (Math.random());
...
How can I convert JSON to CSV?
...this:
{
"pk": 22,
"model": "auth.permission",
"codename": "add_logentry",
"content_type": 8,
"name": "Can add log entry"
},
......]
Here is my code to generate CSV from that:
import csv
import json
x = """[
{
"pk": 22,
"model": "auth.permission",
...
Characters allowed in a URL
...738 specification:
Thus, only alphanumerics, the special characters "$-_.+!*'(),", and
reserved characters used for their reserved purposes may be used
unencoded within a URL.
EDIT: As @Jukka K. Korpela correctly points out, this RFC was updated by RFC 3986.
This has expanded and clarified...
Python 2.7: Print to File
...If you want to use the print function in Python 2, you have to import from __future__:
from __future__ import print_function
But you can have the same effect without using the function, too:
print >>f1, 'This is a test'
...
Is gettimeofday() guaranteed to be of microsecond resolution?
...fectively makes the answer to your question no.
You should look into clock_gettime(CLOCK_MONOTONIC) for timing intervals. It suffers from several less issues due to things like multi-core systems and external clock settings.
Also, look into the clock_getres() function.
...
How to convert a Django QuerySet to a list
...
You could do this:
import itertools
ids = set(existing_answer.answer.id for existing_answer in existing_question_answers)
answers = itertools.ifilter(lambda x: x.id not in ids, answers)
Read when QuerySets are evaluated and note that it is not good to load the whole result int...