commit https://github.com/vim/vim/commit/6244a0fc29163ba1c734f92b55a89e01e6cf2a67 Author: Bram Moolenaar <Bram@vim.org> Date: Thu Apr 14 14:09:25 2016 +0200 patch 7.4.1729 Problem: The Perl interface cannot use 'print' operator for writing directly in standard IO. Solution: Add a minimal implementation of PerlIO Layer feature and try to use it for STDOUT/STDERR. (Damien)

is<F4>foo
{'silent': 0, 'noremap': 0, 'lhs': 'foo<C-V>', 'mode': ' ', 'nowait': 0, 'expr': 0, 'sid': 0, 'rhs': 'is<F4>foo', 'buffer': 0}
{'silent': 1, 'noremap': 1, 'lhs': 'bar', 'mode': 'v', 'nowait': 0, 'expr': 1, 'sid': 0, 'rhs': 'isbar', 'buffer': 1}
{'silent': 0, 'noremap': 0, 'lhs': 'foo', 'mode': ' ', 'nowait': 1, 'expr': 0, 'sid': 0, 'rhs': 'bar', 'buffer': 1}
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