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Is there a standard function to check for null, undefined, or blank variables in JavaScript?
...n the specification at the ToBoolean section.
Furthermore, if you do not know whether a variable exists (that means, if it was declared) you should check with the typeof operator. For instance
if( typeof foo !== 'undefined' ) {
// foo could get resolved and it's defined
}
If you can be sure ...
jQuery Determine if a matched class has a given id
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I would probably use $('.mydiv').is('#foo'); That said if you know the Id why wouldnt you just apply it to the selector in the first place?
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Regex - Does not contain certain Characters
...special characters: the shell interprets some of them. Look to see if you now have a file named ']+$' in your directory. Put the entire regex inside single quotes to make it work.
– Ned Batchelder
Sep 11 '17 at 23:50
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In Eclipse, what can cause Package Explorer “red-x” error-icon when all Java sources compile without
...ackage directories had accidentally been copied so that an extra directory now existed called "Copy of dagskra" containing Java files with wrong package declarations. In addition the errors in this "new" directory don't show up with a "red-x" in the package that it exists in:
Snapshot from Package ...
How to extract year and month from date in PostgreSQL without using to_char() function?
... That's right. U can use to compare: date(date_trunc( 'month', now())) = to_Date(5::varchar || ' ' || 2017::varchar, 'mm YYYY')
– Alejandro Salamanca Mazuelo
May 19 '17 at 21:22
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What is the most efficient way to store a list in the Django models?
...izing and deserializing values from the database to Python and vice versa. Now you can easily import and use our custom field in the model class:
from django.db import models
from custom.fields import SeparatedValuesField
class Person(models.Model):
name = models.CharField(max_length=64)
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alternatives to REPLACE on a text or ntext datatype
... Just a note that the 2005+ nvarchar(max) doesn't have 4000 char limit. I know it's obvious (now, to me), but I first read it as if both answers had that limit.
– goodeye
Jan 17 '19 at 22:55
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How to display HTML tags as plain text [duplicate]
... the <>s:
&lt;strong&gt;Look just like this line - so then know how to type it&lt;/strong&gt;
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Is there a SASS.js? Something like LESS.js?
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Now we just need a C++ to Ruby compiler and we can unify the codebase.
– joeytwiddle
Aug 23 '15 at 23:59
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Collection was modified; enumeration operation may not execute
...ked. Also try using a for instead of a foreach, See this and this. Let me know if that solves it.
– Mohammad Sepahvand
Apr 21 '14 at 6:09
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