Sign Up to our social questions and Answers Engine to ask questions, answer people’s questions, and connect with other people.
Login to our social questions & Answers Engine to ask questions answer people’s questions & connect with other people.
Lost your password? Please enter your email address. You will receive a link and will create a new password via email.
Please briefly explain why you feel this question should be reported.
Please briefly explain why you feel this answer should be reported.
Please briefly explain why you feel this user should be reported.
I often see pprograms like this, where Int64 is an absolute performance killer on 32-bit platforms. My question is now:
If I need a specific word length for my task (in my case a RNG), is Int64 efficient on 64-bit platforms or will it still use the C-calls? And how efficient is converting an Int64 to an Int?
on a 64bit system Int64 should be fine, I don’t know for sure though.
More importantly if you’re doing Crypto or random-number-generation you MUST use the data type that the algorithm says to use, also be careful of signed-ness. If you do-not do this you will have the wrong results, which might mean that your cryptography is not secure or your random number generator is not really random (RNGs are hard, and many look random but aren’t).
For any other type of work use Integer wherever you can, or even better, make your program polymorphic using the Integral type-class. Then if you think your program is slower than it should be profile it to determine where you should concentrate when you try to speed it up. if you use the Integral type-class changing from Integer to Int is easy. Haskell should be smart enough to specialize (most) code that uses polymorphism to avoid overheads.