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Capturing multiple line output into a Bash variable
...y as it is represented in the variable — newlines, tabs, multiple blanks and all — whereas (2) the unquoted version (echo $RESULT) replaces each sequence of one or more blanks, tabs and newlines with a single space. Thus (1) preserves the shape of the input variable, whereas (2) creates a potent...
Difference between Observer, Pub/Sub, and Data Binding
...hat is the difference between the Observer Pattern , Publish/Subscribe , and Data Binding ?
4 Answers
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Git format-patch to be svn compatible?
...ch with git diff --no-prefix master..branch > somefile.diff, the master and branch part are optional, depends how you want to get your diffs.
Send it wherever and apply with patch -p0 < somefile.diff.
It always seems to work fine for me and seems to be the simplest method that I've come acr...
Using a BOOL property
...s used with heap allocated NSObjects like NSString*, NSNumber*, UIButton*, and etc, because memory managed accessors are created for free. When you create a BOOL, the value is always allocated on the stack and does not require any special accessors to prevent memory leakage. isWorking is simply th...
How to pass parameters on onChange of html select
I am a novice at JavaScript and jQuery. I want to show one combobox-A, which is an HTML <select> with its selected id and contents at the other place on onChange().
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Bundler not including .min files
...tweaked behaviour has changed in Microsoft.AspNet.Web.Optimization package and the tweak does not work anymore, as pointed out by many commenters. Right now I cannot reproduce the issue at all with the version 1.1.3 of the package.
Please see sources of System.Web.Optimization.BundleCollection (you...
How does RewriteBase work in .htaccess
...
In my own words, after reading the docs and experimenting:
You can use RewriteBase to provide a base for your rewrites. Consider this
# invoke rewrite engine
RewriteEngine On
RewriteBase /~new/
# add trailing slash if missing
rewriteRule ^(([a-z0-9\-...
Selecting multiple columns in a pandas dataframe
...1 = df[['a', 'b']]
Alternatively, if it matters to index them numerically and not by their name (say your code should automatically do this without knowing the names of the first two columns) then you can do this instead:
df1 = df.iloc[:, 0:2] # Remember that Python does not slice inclusive of the ...
“:” (colon) in C struct - what does it mean? [duplicate]
What does :1 and :8 mean?
3 Answers
3
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How do I check for null values in JavaScript?
... !user){
Which will check for empty strings (""), null, undefined, false and the numbers 0 and NaN
Please note that if you are specifically checking for numbers it is a common mistake to miss 0 with this method, and num !== 0 is preferred (or num !== -1 or ~num (hacky code that also checks agains...