@Nullable
private <D extends DeclarationDescriptor> D substitute(@Nullable D descriptor) {
if (descriptor == null) return null;
if (substitutor.isEmpty()) return descriptor;
if (substitutedDescriptors == null) {
substitutedDescriptors = Maps.newHashMap();
}
DeclarationDescriptor substituted = substitutedDescriptors.get(descriptor);
if (substituted == null && !substitutedDescriptors.containsKey(descriptor)) {
substituted = descriptor.substitute(substitutor);
//noinspection ConstantConditions
substitutedDescriptors.put(descriptor, substituted);
}
//noinspection unchecked
return (D) substituted;
}
public static <D extends CallableDescriptor> D alphaConvertTypeParameters(D candidate) {
return (D) candidate.substitute(MAKE_TYPE_PARAMETERS_FRESH);
}