Greetings, On Saturday, February 09, 2002 3:57:33 PM Karl B Buchner wrote: >> Well, your problem is pretty straightforward: >> You have 8 bits and you're trying to see whether number 16 is >> set. > So flags.test(x) will test (1<<x), and not x? test will test whether bit number x is set. Whether it does this by looking at (1 << x) internally or not is of little interest. :o) > What about |= operator and such? operator |= takes a right-hand side of const bitset<bits>& so it OR's two bitsets of comparative size. As for the other they are quite nicely listed in the standard and in a lot of books pertaining to the standard library [1]. > In other words, do some of the bitset funcs and operators > take the number of the bit and others the bit itself? No, they all take either the number of the bit or another bitset. > if i wanted to test both bit #4 and bit #5 would i have > to do two checks (flags.set(4) || flags.set(5)) instead of > the one for standard bitvectors (IS_SET((1 << 4) | (1 << 5)))? Well, I hope that you'd test rather than set the bits to see whether they are set. :o) if (flags.test(4) || flags.test(5)) is the same as if (IS_SET(flags, (1 << 4)) || IS_SET(flags, (1 << 5))) > sorry if its a bit question laden, but I'm prety new to c++ See [1]. :o) [1]: A good and thorough reference is always a must when you try to delve into some topic, particularly C++ as it isn't too trivial. :o) So I'd recommend picking up at least the following two books: Stroustrup, Bjarne: The C++ Programming Language, 3rd. Edition Josuttis, Nicolai M.: The C++ Standard Library: A Tutorial and Reference Some might differ in their preference for a standard library reference, others might argue that Stroustrup gives an adequate introduction to the standard library, but in my opinion, Josuttis give a nice and complete introduction to using the standard c++ library in terms understandable for people at the beginning stages through to more advanced programmers. -- Yours truly, Henrik Stuart (http://www.unprompted.com/hstuart/) -- +---------------------------------------------------------------+ | FAQ: http://qsilver.queensu.ca/~fletchra/Circle/list-faq.html | | Archives: http://post.queensu.ca/listserv/wwwarch/circle.html | | Newbie List: http://groups.yahoo.com/group/circle-newbies/ | +---------------------------------------------------------------+
This archive was generated by hypermail 2b30 : 06/25/03 PDT