Instead of forbidding std::map<const std::type_info*, ...> outright (which
includes LLRegistry<const std::type_info*, ...> and LLRegistrySingleton<const
std::type_info*, ...>), try to make it work by specializing std::less<const
std::type_info*> to use std::type_info::before().
Make LLRegistryDefaultComparator<T> use std::less<T> so it can capitalize on
that specialization.
Although LLRegistry and LLRegistrySingleton have always defined a COMPARATOR
template parameter, it wasn't used for the underlying map. Therefore every
type, including any pointer type, was being compared using std::less. This
happens to work most of the time -- but is tripping us up now.
Pass COMPARATOR to underlying std::map. Fix a couple minor bugs in
LLRegistryDefaultComparator (never before used!). Specialize for const char*.
Remove CompareTypeID and LLCompareTypeID because we now actively forbid using
LLRegistry<std::type_info*, ...>; remove only known reference
(LLWidgetNameRegistry definition).
Per discussion with Richard, accept the type key for insert() and find() as a
template parameter rather than as std::type_info*. This permits (e.g.) some
sort of compile-time prehashing for common types, without changing the API.
Eliminate iterators from the API altogether, thus avoiding costs associated
with transform_iterator.
Fix existing references in llinitparam.h.
In a number of places, the viewer uses a lookup based on std::type_info*. We
used to use std::map<std::type_info*, whatever>. But on Linux,
&typeid(SomeType) can produce different pointer values, depending on the
dynamic load module in which the code is executed. Introduce
LLTypeInfoLookup<T>, with an API that deliberately mimics
std::map<std::type_info*, T>. LLTypeInfoLookup::find() first tries an
efficient search for the specified std::type_info*. But if that fails, it
scans the underlying container for a match on the std::type_info::name()
string. If found, it caches the new std::type_info* to optimize subsequent
lookups with the same pointer.
Use LLTypeInfoLookup instead of std::map<std::type_info*, ...> in
llinitparam.h and llregistry.h.
Introduce LLSortedVector<KEY, VALUE>, a std::vector<std::pair<KEY, VALUE>>
maintained in sorted order with binary-search lookup. It presents a subset of
the std::map<KEY, VALUE> API.
Nat Goodspeed