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Best way to give a variable a default value (simulate Perl ||, ||= )
... to do $var = @$var ?: 'default value'; If so, why? Given that the only "error" could be that $var isn't set, and that we don't care if $var isn't set...
– Codemonkey
Nov 13 '15 at 14:14
...
搭建高可用mongodb集群（三）—— 深入副本集内部机制 - 大数据 & AI - 清...
...以触发。
初始化一个副本集时。
副本集和主节点断开连接，可能是网络问题。
主节点挂掉。
选举还有个前提条件，参与选举的节点数量必须大于副本集总节点数量的一半，如果已经小于一半了所有节点保持只读状态。
...
What is the id( ) function used for?
... Python objects.
Is it the same with memory addresses in C?
Conceptually, yes, in that they are both guaranteed to be unique in their universe during their lifetime. And in one particular implementation of Python, it actually is the memory address of the corresponding C object.
If yes, wh...
How to get disk capacity and free space of remote computer
...u run the powershell under task scheduler
2) You may get Access is denied errors errors trying to used "get-WmiObject" on remote computers (depending on your infrastructure setup, of course)
The alternative that doesn't suffer from these issues is to use GetDiskFreeSpaceEx with a UNC path:
functi...
How can I trigger a JavaScript event click
...eType 9 = DOCUMENT_NODE
doc = node;
} else {
throw new Error("Invalid node passed to fireEvent: " + node.id);
}
if (node.dispatchEvent) {
// Gecko-style approach (now the standard) takes more work
var eventClass = "";
// Different events have di...
How Big can a Python List Get?
...ist takes up 4 bytes or on a 64 bit it's 8 bytes, Python would give you an error if you attempt to make a list larger than maxsize/8 on a 64-bit system or maxsize/4 on a 32-bit system.
– thorr18
Sep 4 at 20:51
...
How to deal with floating point number precision in JavaScript?
...bers like 1/10 without realizing that they wouldn't even blink at the same error if it occurred with 1/3.
If the first point really applies to you, use BigDecimal for JavaScript, which is not elegant at all, but actually solves the problem rather than providing an imperfect workaround.
...
CodeIgniter removing index.php from url
...index.php/about-us and domain.com/index.php?/about-us which generating SEO error i.e duplicate title tag and duplicate meta description
– Musaddiq Khan
Jun 26 '14 at 12:35
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How can I count the occurrences of a list item?
... very late to the party but wouldn't following code throw an error if a list contained more than one instance of i, because it will try to enter multiple keys of same value in a dictionary. dict((i, a.count(i)) for i in a)
– rp1
Sep 16 '19 a...
Create an empty list in python with certain size
...nately if you want to create a list-of-lists you will run into referencing errors. Example in Python 2.7.6:
>>> a = [[]]*10
>>> a
[[], [], [], [], [], [], [], [], [], []]
>>> a[0].append(0)
>>> a
[[0], [0], [0], [0], [0], [0], [0], [0], [0], [0]]
>>>
...