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What is the easiest way to duplicate an activerecord record?
... Does this still work in Rails 3.1.0.beta? When I do q = p.clone, and then p == q, I get true back. On the other hand, if I use q = p.dup, I get false back when comparing them.
– Juno Woods
Feb 8 '11 at 2:10
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How do you debug PHP scripts? [closed]
...nto the code is a much better way to debug then the old method of var_dump and print at various points to see where your flow goes wrong. When all else fails though and all I have is SSH and vim I still var_dump()/die() to find where the code goes south.
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Git pull a certain branch from GitHub
...have a project with multiple branches. I've been pushing them to GitHub , and now that someone else is working on the project I need to pull their branches from GitHub. It works fine in master. But say that someone created a branch xyz . How can I pull branch xyz from GitHub and merge it into br...
Type Checking: typeof, GetType, or is?
...y_a_dog = new Dog();
Foo(probably_a_dog); // this calls Foo<Animal> and returns "Animal"
Foo<Animal>(probably_a_dog); // this is exactly the same as above
Foo<Dog>(probably_a_dog); // !!! This will not compile. The parameter expects a Dog, you cannot pass in an Animal.
Foo(defini...
How do I get the number of days between two dates in JavaScript?
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Here is a quick and dirty implementation of datediff, as a proof of concept to solve the problem as presented in the question. It relies on the fact that you can get the elapsed milliseconds between two dates by subtracting them, which coerc...
Mapping two integers to one, in a unique and deterministic way
Imagine two positive integers A and B. I want to combine these two into a single integer C.
18 Answers
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boolean in an if statement
...-empty string value, any object or array reference, etc...
On the other hand:
if (booleanValue === true)
This will only satisfy the if condition if booleanValue is exactly equal to true. No other truthy value will satisfy it.
On the other hand if you do this:
if (someVar == true)
Then, wha...
Error when trying to obtain a certificate: The specified item could not be found in the keychain
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I solved it. Ensure you are in the "Certificates" section and you select "Apple Worldwide Developer Relations Certification Authority" before requesting a certificate.
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What is tail call optimization?
... space as (fact 3). This is not the case with the non-tail-recursive fact, and as such large values may cause a stack overflow.
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Is it possible to serialize and deserialize a class in C++?
Is it possible to serialize and deserialize a class in C++?
13 Answers
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