* guix/inferior.scm, guix/scripts/repl.scm, tests/inferior.scm: New files. * Makefile.am (MODULES): Add 'guix/scripts/repl.scm' and 'guix/inferior.scm'. (SCM_TESTS): Add 'tests/inferior.scm'. * doc/guix.texi (Invoking guix repl): New node.