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Detecting an undefined object property
...ined`");
}
To check if an object does not actually have such a property, and will therefore return undefined by default when you try and access it:
if(!o.hasOwnProperty('myProperty')) {
alert("myProperty does not exist");
}
To check if the value associated with an identifier is the special va...
How do I replace a character at a particular index in JavaScript?
I have a string, let's say Hello world and I need to replace the char at index 3. How can I replace a char by specifying a index?
...
namedtuple and default values for optional keyword arguments
...
I subclassed namedtuple and overrode the __new__ method:
from collections import namedtuple
class Node(namedtuple('Node', ['value', 'left', 'right'])):
__slots__ = ()
def __new__(cls, value, left=None, right=None):
return super(Nod...
Serializing a list to JSON
...atively, other, less mainstream options are available like Utf8Json parser and Jil: These may offer superior performance, if you really need it but, you will need to install their respective packages.
If stuck using .Net Core 2.2 or earlier;
Default to using Newtonsoft JSON.Net as your first choic...
Why would you use an ivar?
...is question asked the other way, such as Must every ivar be a property? (and I like bbum's answer to this Q).
7 Answers
...
How do I change the cursor between Normal and Insert modes in Vim?
...
A popular option to indicate switching to and from Insert mode is
toggling the cursorline option, which is responsible for whether
the current screen line is highlighted (see :help cursorline):
:autocmd InsertEnter,InsertLeave * set cul!
or, alternatively:
:autocmd ...
What does %~dp0 mean, and how does it work?
I find %~dp0 very useful, and I use it a lot to make my batch files more portable.
7 Answers
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Rails raw SQL example
How can I convert this code to raw sql and use in rails? Because When I deploy this code in heroku,there is a request timeout error.I think this will be faster if I use raw sql.
...
How can foreign key constraints be temporarily disabled using T-SQL?
Are disabling and enabling foreign key constraints supported in SQL Server? Or is my only option to drop and then re-create the constraints?
...
To switch from vertical split to horizontal split fast in Vim
...an you switch your current windows from horizontal split to vertical split and vice versa in Vim?
8 Answers
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