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What is the purpose of base 64 encoding and why it used in HTTP Basic Authentication?
...pedia page for HTTP Basic Authentication:
While encoding the user name and password with the Base64 algorithm typically makes them unreadable by the naked eye, they are as easily decoded as they are encoded. Security is not the intent of the encoding step. Rather, the intent of the encoding is t...
Benefits of using the conditional ?: (ternary) operator
What are the benefits and drawbacks of the ?: operator as opposed to the standard if-else statement. The obvious ones being:
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Get first and last day of month using threeten, LocalDate
I have a LocalDate which needs to get the first and last day of the month.
How do I do that?
10 Answers
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What's the difference between a web site and a web application? [closed]
I'm stumped trying to come up to a difference between a website and a web application for myself. As I see it, a web site points to a specific page and a web application is more of some sort of 'portal' to content and information.
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What is the difference between .*? and .* regular expressions?
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It is the difference between greedy and non-greedy quantifiers.
Consider the input 101000000000100.
Using 1.*1, * is greedy - it will match all the way to the end, and then backtrack until it can match 1, leaving you with 1010000000001.
.*? is non-greedy. * w...
How do I clone a Django model instance object and save it to the database?
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Just change the primary key of your object and run save().
obj = Foo.objects.get(pk=<some_existing_pk>)
obj.pk = None
obj.save()
If you want auto-generated key, set the new key to None.
More on UPDATE/INSERT here.
Official docs on copying model instances: h...
Check folder size in Bash
I'm trying to write a script that will calculate a directory size and if the size is less than 10GB, and greater then 2GB do some action. Where do I need to mention my folder name?
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Why don't C++ compilers define operator== and operator!=?
...ison or a deep (internal) comparison.
It's safer to just not implement it and let the programmer do that themselves. Then they can make all the assumptions they like.
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Apply a function to every row of a matrix or a data frame
Suppose I have a n by 2 matrix and a function that takes a 2-vector as one of its arguments. I would like to apply the function to each row of the matrix and get a n-vector. How to do this in R?
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what is the difference between ?:, ?! and ?= in regex?
I searched for the meaning of these expressions but couldn't understand the exact difference between them.
This is what they say:
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