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Collection versus List what should you use on your interfaces?
... the question as to why not List<T>, The reasons are future-proofing and API simplicity.
Future-proofing
List<T> is not designed to be easily extensible by subclassing it; it is designed to be fast for internal implementations. You'll notice the methods on it are not virtual and so can...
How does “do something OR DIE()” work in PHP?
I'm writing a php app to access a MySQL database, and on a tutorial, it says something of the form
4 Answers
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Difference between a theta join, equijoin and natural join
I'm having trouble understanding relational algebra when it comes to theta joins, equijoins and natural joins. Could someone please help me better understand it? If I use the = sign on a theta join is it exactly the same as just using a natural join?
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ImportError: No module named site on Windows
... does not include source) . I then ran the installer, selected 'All Users' and all was fine. I installed Python into the default location:
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What does “static” mean in C?
...l for cases where a function needs to keep some state between invocations, and you don't want to use global variables. Beware, however, this feature should be used very sparingly - it makes your code not thread-safe and harder to understand.
(2) Is used widely as an "access control" feature. If you...
Difference between jQuery parent(), parents() and closest() functions
...ches the selector, up
from the DOM tree. Begins from the current element and travels up.
parent() selects one element up (single level up) the DOM tree.
parents() method is similar to parent() but selects all the
matching elements up the DOM tree. Begins from the parent element and tr...
Font Awesome icon inside text input element
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You're right. :before and :after pseudo content is not intended to work on replaced content like img and input elements. Adding a wrapping element and declare a font-family is one of the possibilities, as is using a background image. Or maybe a ht...
Test if a vector contains a given element
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Both the match() (returns the first appearance) and %in% (returns a Boolean) functions are designed for this.
v <- c('a','b','c','e')
'b' %in% v
## returns TRUE
match('b',v)
## returns the first location of 'b', in this case: 2
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foldl versus foldr behavior with infinite lists
...r folding a list of n values [x1, x2, x3, x4 ... xn ] with some function f and seed z.
foldl is:
Left associative: f ( ... (f (f (f (f z x1) x2) x3) x4) ...) xn
Tail recursive: It iterates through the list, producing the value afterwards
Lazy: Nothing is evaluated until the result is needed
Backw...
Convert Mercurial project to Git [duplicate]
...it history intact. My current solution was to just remove hg related files and then git init && add manually the files I needed, but that would not keep the history. Are there any solutions to this?
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