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Code Issues Releases Activity

remove nkeys from Ordering slightly faster

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This commit is contained in:
Dwight 2011-06-16 14:46:27 -04:00
parent 73b97fda11
commit ac1232db80
1 changed files with 15 additions and 8 deletions
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23
bson/ordering.h
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@ -19,15 +19,22 @@
namespace mongo {
/** A precomputation of a BSON key pattern.
// todo: ideally move to db/ instead of bson/, but elim any dependencies first
/** A precomputation of a BSON index or sort key pattern. That is something like:
{ a : 1, b : -1 }
The constructor is private to make conversion more explicit so we notice where we call make().
Over time we should push this up higher and higher.
*/
*/
class Ordering {
const unsigned bits;
const unsigned nkeys;
Ordering(unsigned b,unsigned n) : bits(b),nkeys(n) { }
unsigned bits;
Ordering(unsigned b) : bits(b) { }
public:
Ordering(const Ordering& r) : bits(r.bits) { }
void operator=(const Ordering& r) {
bits = r.bits;
}
/** so, for key pattern { a : 1, b : -1 }
get(0) == 1
get(1) == -1
@ -39,12 +46,12 @@ namespace mongo {
// for woCompare...
unsigned descending(unsigned mask) const { return bits & mask; }
operator string() const {
/*operator string() const {
StringBuilder buf(32);
for ( unsigned i=0; i<nkeys; i++)
buf.append( get(i) > 0 ? "+" : "-" );
return buf.str();
}
}*/
static Ordering make(const BSONObj& obj) {
unsigned b = 0;
@ -59,7 +66,7 @@ namespace mongo {
b |= (1 << n);
n++;
}
return Ordering(b,n);
return Ordering(b);
}
};