Would there be any interest in using picocli ( https://github.com/remkop/picocli) as the command line parser in `org.apache.tools.ant.Main`?
Picocli has support for @-files (https://picocli.info/#AtFiles ) to handle cases where the length of the command line exceeds the OS limitations. (I believe there was a recent request for this feature on the user list.) The Main class will likely become shorter and easier to maintain. As a bonus, picocli generates nice-looking help with ANSI colors and can generate completion scripts to get command line completion on bash and zsh shells. The trade-off is the additional external dependency. Picocli is relatively new (1.0 released in Aug 2017) but has growing adoption and is used in Groovy, Micronaut, JUnit 5 and CheckStyle. I’d be happy to provide a PR if there’s interest. Remko Popma
