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Difference between Array and List in scala
... is that arrays are nonvariant and lists are covariant. But what about performance and some other characteristics?
3 Answe...
Do regular expressions from the re module support word boundaries (\b)?
While trying to learn a little more about regular expressions, a tutorial suggested that you can use the \b to match a word boundary. However, the following snippet in the Python interpreter does not work as expected:
...
How do I pass a method as a parameter in Python
...em around the way you do variables. In fact, you can think about a method (or function) as a variable whose value is the actual callable code object.
Since you asked about methods, I'm using methods in the following examples, but note that everything below applies identically to functions (except wi...
Why does flowing off the end of a non-void function without returning a value not produce a compiler
Ever since I realized many years ago, that this doesn't produce an error by default (in GCC at least), I've always wondered why?
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Which parts of Real World Haskell are now obsolete or considered bad practice?
In the chapter 19 of Real World Haskell a lot of the examples now fail due to the change of Control.Exception .
1 Answer...
How to do a LIKE query in Arel and Rails?
...
This is how you perform a like query in arel:
users = User.arel_table
User.where(users[:name].matches("%#{user_name}%"))
PS:
users = User.arel_table
query_string = "%#{params[query]}%"
param_matches_string = ->(param){
users[param].ma...
How to find where a method is defined at runtime?
...his from Dave Thomas while teaching Advanced Ruby Studio
# Makes the case for separating method definitions into
# modules, especially when enhancing built-in classes.
module Perpetrator
def crime
end
end
class Fixnum
include Perpetrator
end
p 2.method(:crime) # The "2" here is an instance o...
Equation (expression) parser with precedence?
I've developed an equation parser using a simple stack algorithm that will handle binary (+, -, |, &, *, /, etc) operators, unary (!) operators, and parenthesis.
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Big-O for Eight Year Olds? [duplicate]
I'm asking more about what this means to my code. I understand the concepts mathematically, I just have a hard time wrapping my head around what they mean conceptually. For example, if one were to perform an O(1) operation on a data structure, I understand that the number of operations it has to p...
Refresh a page using JavaScript or HTML [duplicate]
How can I refresh a page using JavaScript or HTML?
8 Answers
8
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