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What is the difference between LR, SLR, and LALR parsers?
...xactly the same table-driven machinery.
Fundamentally, the parsing algorithm collects the next input token T, and consults the current state S (and associated lookahead, GOTO, and reduction tables) to decide what to do:
SHIFT: If the current table says to SHIFT on the token T, the pair (S,T) is...
Checking if a variable is defined?
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Use the defined? keyword (documentation). It will return a String with the kind of the item, or nil if it doesn’t exist.
>> a = 1
=> 1
>> defined? a
=> "local-variable"
>> defined? b
=> nil
>> defined? nil
=> "nil"
>> ...
Transferring ownership of an iPhone app on the app store
My team and I have an app which we're going to be submitting to the store pretty soon, but we know that we'll be selling the app to another company in the near future. Does anyone have any experience with moving an app's ownership to another account?
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Is there a good reason I see VARCHAR(255) used so often (as opposed to another length)?
...gth of 255 is chosen so often, other than being a nice round number ? Is it a holdout from some time in the past when there was a good reason (whether or not it applies today)?
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Is mathematics necessary for programming? [closed]
I happened to debate with a friend during college days whether advanced mathematics is necessary for any veteran programmer. He used to argue fiercely against that. He said that programmers need only basic mathematical knowledge from high school or fresh year college math, no more no less, and that ...
Can I get “&&” or “-and” to work in PowerShell?
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In CMD, '&&' means "execute command 1, and if it succeeds, execute command 2". I have used it for things like:
build && run_tests
In PowerShell, the closest thing you can do is:
(build) -and (run_tests)
It has the same logic, but the output text from the c...
What is the >>>= operator in C?
...les and runs. What is this >>>= operator and the strange 1P1 literal? I have tested in Clang and GCC. There are no warnings and the output is "???"
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When should I mock?
... not sure I have a feeling about when/where to use mocking - especially as it would apply to this scenario here .
4 Answer...
Disadvantages of Test Driven Development? [closed]
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Several downsides (and I'm not claiming there are no benefits - especially when writing the foundation of a project - it'd save a lot of time at the end):
Big time investment. For the simple case you lose about 20% of the actual implementation, but for complicated cases you lose m...
Set width of a “Position: fixed” div relative to parent div
I'm trying to give a div (position: fixed) the width of 100% (relating to it's parent div). But I've got some problems...
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