boostorg/program_options — pull request #8 by mjdecker (2014-12-30 00:27:03+00:00)
Title: Ticket #4510: implicit_value and positional options conflict

Add a has_implicit_value method to check if an implicit_value was set. This is used to avoid processing positional arguments for options with implicit_value.

The change seems simple enough, however, I am not nearly as familiar with the library, and I could not build this using the git repo to test it, as there seems to be some problem with building all the boost libraries on the main git repo. However, I did test it by applying the changes to the latest release of boost (1.57.0) and it seems to work fine.