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How to check if a variable is null or empty string or all whitespace in JavaScript?
I need to check to see if a variable is null or has all empty spaces or is just blank ("").
12 Answers
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What is the difference between require() and library()?
What is the difference between require() and library() ?
8 Answers
8
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How do I daemonize an arbitrary script in unix?
...h this is standard out and standard error both get sent to ./nohup.out, so if you start several scripts in this manor their output will be intertwined. A better command would be:
nohup yourScript.sh script args >script.out 2>script.error&
This will send standard out to the file of your ...
How to compare software version number using js? (only number)
...rom the input strings and then compare pairs of parts from the two arrays; if the parts are not equal we know which version is smaller.
There are a few of important details to keep in mind:
How should the parts in each pair be compared? The question wants to compare numerically, but what if we ha...
Why can't R's ifelse statements return vectors?
I've found R's ifelse statements to be pretty handy from time to time. For example:
9 Answers
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Why #define TRUE (1==1) in a C boolean macro instead of simply as 1?
... approach will use the actual boolean type (and resolve to true and false) if the compiler supports it. (specifically, C++)
However, it would be better to check whether C++ is in use (via the __cplusplus macro) and actually use true and false.
In a C compiler, this is equivalent to 0 and 1.
(note ...
Test if a variable is a list or tuple
In python, what's the best way to test if a variable contains a list or a tuple? (ie. a collection)
13 Answers
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How to split one string into multiple variables in bash shell? [duplicate]
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If your solution doesn't have to be general, i.e. only needs to work for strings like your example, you could do:
var1=$(echo $STR | cut -f1 -d-)
var2=$(echo $STR | cut -f2 -d-)
I chose cut here because you could simply ex...
Add a column to a table, if it does not already exist
...an use a similar construct by using the sys.columns table io sys.objects.
IF NOT EXISTS (
SELECT *
FROM sys.columns
WHERE object_id = OBJECT_ID(N'[dbo].[Person]')
AND name = 'ColumnName'
)
share
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Angularjs ng-model doesn't work inside ng-if
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The ng-if directive, like other directives creates a child scope. See the script below (or this jsfiddle)
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.0rc1/angular.min.js"></script>
<script...