Return the namespace prefix at the specified index in the prefix stack, where an index of 0 is the oldest prefix on the stack. If index is negative, return the prefix at position 'numPrefixes() - index'. Thus, an index of -1 will return the most recent prefix on the stack (i.e., the top of the stack). The behavior is undefined if index > numPrefixes() or index < -numPrefixes().
Declared in <balxml_prefixstack.h>
char const*
namespacePrefixByIndex(int index) const;