Using | in a vim mapping

When you want to type | in a vim mapping, you need to use <bar> instead of | sign. An example mapping can be :

nnoremap <Leader>r :terminal shell++ ./a.out <bar> beautifyLogs<CR>

This takes the output of a.out to a custom beautifyLogs utitlity, which will output a beautiful logs into a vim buffer and you can now scroll through it

Reference

• Mapping a command not the same as writing command in vim terminal