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Chrome sendrequest error: TypeError: Converting circular structure to JSON
...mit": null,
"size": 0,
"chunks": [],
"writable": true,
"readable": false,
"_events": {
"pipe": [null, null],
"error": [null]
},
"before": [null],
"after": [],
"response": {
"output": [],
"outputEncodings": [],
"writable": true,
"_last": false,
"chunkedEncoding": false,
...
How to get the original value of an attribute in Rails
...
Before rails 5.1
Appending _was to your attribute will give you the previous value.
For rails 5.1+
Copied from Lucas Andrade's answer below: https://stackoverflow.com/a/50973808/9359123
Appending _was is deprecated in rails 5.1, now you should ap...
Google Tag Manager 入门指南 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...页脚，如：footer.inc：
<script type=”text/javascript”>
var _gaq = _gaq || [];
_gaq.push(["_setAccount", "UA-XXXXXX-1"]);
_gaq.push(["_trackPageview"]);
(function() {
var ga = document.createElement(“script”); ga.type = “text/javascript”; ga.async = true;
ga.src = (...
How to split a string literal across multiple lines in C / Objective-C?
...ll lines in C can be split into multiple lines using \.
Plain C:
char *my_string = "Line 1 \
Line 2";
Objective-C:
NSString *my_string = @"Line1 \
Line2";
Better approach
There's a better approach that works just for strings.
Plain C:
char *my_str...
Any gotchas using unicode_literals in Python 2.6?
...ng: utf-8
name = 'helló wörld from two'
one.py
# encoding: utf-8
from __future__ import unicode_literals
import two
name = 'helló wörld from one'
print name + two.name
The output of running python one.py is:
Traceback (most recent call last):
File "one.py", line 5, in <module>
...
How to convert list of tuples to multiple lists?
...
xs, ys = [x for x, y in zs], [y for x, y in zs]
return xs, ys
if __name__ == '__main__':
from timeit import timeit
setup_string='''\
N = 2000000
xs = list(range(1, N))
ys = list(range(N+1, N*2))
zs = list(zip(xs, ys))
from __main__ import t1, t2, t3
'''
print(f'zip:\t\t{timeit(...
Named routes _path vs _url
...
_path helpers provide a site-root-relative path. You should probably use this most of the time.
_url helpers provide an absolute path, including protocol and server name. I've found that I mainly use these in emails when cre...
Is it possible to declare two variables of different types in a for loop?
...:
auto [vec, i32] = std::tuple{std::vector<int>{3, 4, 5}, std::int32_t{12}}
A specific application of this is iterating over a map, getting the key and value,
std::unordered_map<K, V> m = { /*...*/ };
for (auto& [key, value] : m) {
// ...
}
See a live example here
C++14: ...
Getter and Setter?
...
You can use php magic methods __get and __set.
<?php
class MyClass {
private $firstField;
private $secondField;
public function __get($property) {
if (property_exists($this, $property)) {
return $this->$property;
}
}
publi...
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...