ANTLR (ANother Tool for Language Recognition) is a powerful parser generator for
reading, processing, executing, or translating structured text or binary files.
It's widely used to build languages, tools, and frameworks. From a grammar,
ANTLR generates a parser that can build parse trees and also generates a
listener interface (or visitor) that makes it easy to respond to the recognition
of phrases of interest.

This port provides C++ target for ANTLR 4. It contains the C++ runtime support
for ANTLR. See the canonical antlr4 repository for in depth detail about how to
use ANTLR 4.