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What kind of virtual machine is BEAM (the Erlang VM)?
...guage. The programs are usually presented to the virtual machine in source form of the guest language, without being fully compiled into machine code beforehand. The runtime engine needs to interpret or translate the program and also fulfill certain functionalities that are abstracted by the languag...
ruby on rails f.select options with custom attributes
I have a form select statement, like this:
5 Answers
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What does it mean to “program to an interface”?
...ava or C#, we already have inheritance and I viewed interfaces as a weaker form of inheritance and thought, "why bother?" In a sense I was right, you can think of interfaces as sort of a weak form of inheritance, but beyond that I finally understood their use as a language construct by thinking of ...
In C++, what is a “namespace alias”?
...n and answer it yourself if that content wasn't on SO yet in an accessible form. But apparently, this is frowned upon?
– Martin B
Jul 31 '09 at 9:17
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Why is f(i = -1, i = -1) undefined behavior?
...erations are unsequenced, there is nothing to say that the instructions performing the assignment cannot be interleaved. It might be optimal to do so, depending on CPU architecture. The referenced page states this:
If A is not sequenced before B and B is not sequenced before A, then
two possib...
Is it worth hashing passwords on the client side
... clear text) and hash to the server
As the server knows its own random information as well as the client's random bits (it got them as clear text), it can perform essentially the same transformation. This protocol makes sure, that nobody listening in this conversation can use the information later...
Adding 'serial' to existing column in Postgres
...quence value set to 0 is clumsy, if not illegal.
Using the three-parameter form of setval would be more appropriate:
-- vvv
SELECT setval('foo_a_seq', coalesce(max(a), 0) + 1, false) FROM foo;
-- ^ ^
-- ...
Why do we use Base64?
...nary - 0s and 1s - but people typically want to communicate with more rich forms data such as text or images. In order to transfer this data between computers it first has to be encoded into 0s and 1s, sent, then decoded again. To take text as an example - there are many different ways to perform th...
Must Dependency Injection come at the expense of Encapsulation?
...d": they're explicitly exposed, and invariants around them are enforced. Information hiding is the better term for the kind of privacy you're referring to, @RonInbar, and it's not necessarily always beneficial (it makes the pasta harder to untangle ;-)).
– Nicholas Blumhardt
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What are enums and why are they useful?
... is for
Programmers to efficiently and correctly express algorithms in a form computers can use.
Maintainers to understand algorithms others have written and correctly make changes.
Enums improve both likelihood of correctness and readability without writing a lot of boilerplate. If you are wil...