inline rai begin() { return rai(_data,_size); }
static inline const rai end() { return rai(); }
bool llsd_equals(const LLSD& lhs, const LLSD& rhs, unsigned bits)
{
// We're comparing strict equality of LLSD representation rather than
// performing any conversions. So if the types aren't equal, the LLSD
// values aren't equal.
if (lhs.type() != rhs.type())
{
return false;
}
// Here we know both types are equal. Now compare values.
switch (lhs.type())
{
case LLSD::TypeUndefined:
// Both are TypeUndefined. There's nothing more to know.
return true;
case LLSD::TypeReal:
// This is where the 'bits' argument comes in handy. If passed
// explicitly, it means to use is_approx_equal_fraction() to compare.
if (bits >= 0)
{
return is_approx_equal_fraction(lhs.asReal(), rhs.asReal(), bits);
}
// Otherwise we compare bit representations, and the usual caveats
// about comparing floating-point numbers apply. Omitting 'bits' when
// comparing Real values is only useful when we expect identical bit
// representation for a given Real value, e.g. for integer-valued
// Reals.
return (lhs.asReal() == rhs.asReal());
#define COMPARE_SCALAR(type) \
case LLSD::Type##type: \
/* LLSD::URI has operator!=() but not operator==() */ \
/* rely on the optimizer for all others */ \
return (! (lhs.as##type() != rhs.as##type()))
COMPARE_SCALAR(Boolean);
COMPARE_SCALAR(Integer);
COMPARE_SCALAR(String);
COMPARE_SCALAR(UUID);
COMPARE_SCALAR(Date);
COMPARE_SCALAR(URI);
COMPARE_SCALAR(Binary);
#undef COMPARE_SCALAR
case LLSD::TypeArray:
{
LLSD::array_const_iterator
lai(lhs.beginArray()), laend(lhs.endArray()),
rai(rhs.beginArray()), raend(rhs.endArray());
// Compare array elements, walking the two arrays in parallel.
for ( ; lai != laend && rai != raend; ++lai, ++rai)
{
// If any one array element is unequal, the arrays are unequal.
if (! llsd_equals(*lai, *rai, bits))
return false;
}
// Here we've reached the end of one or the other array. They're equal
// only if they're BOTH at end: that is, if they have equal length too.
return (lai == laend && rai == raend);
}
case LLSD::TypeMap:
{
// Build a set of all rhs keys.
std::set<LLSD::String> rhskeys;
for (LLSD::map_const_iterator rmi(rhs.beginMap()), rmend(rhs.endMap());
rmi != rmend; ++rmi)
{
rhskeys.insert(rmi->first);
}
// Now walk all the lhs keys.
for (LLSD::map_const_iterator lmi(lhs.beginMap()), lmend(lhs.endMap());
lmi != lmend; ++lmi)
{
// Try to erase this lhs key from the set of rhs keys. If rhs has
// no such key, the maps are unequal. erase(key) returns count of
// items erased.
if (rhskeys.erase(lmi->first) != 1)
return false;
// Both maps have the current key. Compare values.
if (! llsd_equals(lmi->second, rhs[lmi->first], bits))
return false;
}
// We've now established that all the lhs keys have equal values in
// both maps. The maps are equal unless rhs contains a superset of
// those keys.
return rhskeys.empty();
}
default:
// We expect that every possible type() value is specifically handled
// above. Failing to extend this switch to support a new LLSD type is
// an error that must be brought to the coder's attention.
LL_ERRS("llsd_equals") << "llsd_equals(" << lhs << ", " << rhs << ", " << bits << "): "
"unknown type " << lhs.type() << LL_ENDL;
return false; // pacify the compiler
}
}
