Quote:I presume that's because CodeWarrior isn't using a vector at all. Is what I'm trying to do valid (I.e. is it a compiler error), or are you not allowed to do this with a vector of bools? For the moment, I'm having to convert the vector into a void* manually, which isn't particularly efficient. Is there some std::copy I could use to do this which would be as efficient as direct pointer access? Cheers, Steve
illegal explicit conversion from 'std::__bit_iterator<Metrowerks::__bitvec_deleter<std::allocator<bool>>, false>' to 'void *'
0
std::vector and bool
Started by Evil Steve, Jul 04 2006 01:24 AM
5 replies to this topic
#1 Moderators - Reputation: 1918
Posted 04 July 2006 - 01:24 AM
Hi all, I'm doing some bit-stuffing code at the moment, and I figured I could use std::vector<bool> to do that, since it's specialised (apparently).
I know this is valid:
std::vector<int> foo;
// Stuff things into foo
int* pData = &foo[0];
Since vector storage is contiguous. However, CodeWarrior spazzes out when I do this:
std::vector<bool> foo;
// Stuff a multiple of 8 bits into foo
void* pData = &foo[0];
The error I get is:
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#3 Anonymous Poster_Anonymous Poster_* Guests - Reputation:
Posted 04 July 2006 - 01:35 AM
There are sometimes when standard namespaces templates just dont do it. I did something like this for a huffman encoding yet using unsigned char*(wrapped inside a class), using malloc instead of new (due to speed, ie remalloc instead of delete[] and then new again).
#4 Moderators - Reputation: 1918
Posted 04 July 2006 - 01:35 AM
Quote:Ah well, that's what I thought. I'll just it my way then.
Original post by rip-off
The bool values in std::vectors<bool> are implemented using single bits. You cannot get a reference or pointer to a bit, so you get an error.
This is the downside to the apparent "optimisation" that is std:vector<bool>/
Thanks for the reply
#6 Moderators - Reputation: 1918
Posted 04 July 2006 - 01:57 AM
Quote:I'm beginning to think that this was a bad idea [smile]
Original post by Will F
What You Should Know about vector<bool> - it ain't pretty
I'll re-write this later maybe.
