Adding a command to Vim - vim

Question

I finally decided to try out Vim, as I am getting increasingly frustrated by GUI editors. So far, I'm loving it, but I can't find any help for a issue I'm having...
I am trying to map the command :Pyrun to :!python % in Vim using cmap. The mapping shows up fine if I type :cmap. However, on typing :Pyrun, I get this error message:
Not an editor command: Pyrun.
Here is what I'm trying in .vimrc:
:autocmd FileType python :cmap Pyrun<cr> !python %<cr>
:autocmd FileType python :cmap Intpyrun<cr> !python -i %<cr>
What can I do to solve this problem?

Answer 1

I would try something like this in your .vimrc or your ftplugin/python_ft.vim
command Pyrun execute "!python %"
command Intpyrun execute "!python -i %"
Then :Pyrun and :Intpyrun should work
You could then map a function key to each
map <F5> :Pyrun<CR>
map <F6> :Intpyrun<CR>

Answer 2

I personally prefer another approach. First create a function receiving the command arguments and then create a command to call the function:
fun! DoSomething( arg ) "{{{
echo a:arg
" Do something with your arg here
endfunction "}}}
command! -nargs=* Meh call DoSomething( '<args>' )
So it would be like
fun! Pyrun( arg ) "{{{
execute '!python ' . expand( '%' )
endfunction "}}}
command! -nargs=* Pyrun call Pyrun( '<args>' )
But, there's a better way to do it in Vim. Use makeprg:
makeprg=python\ %
Just type :make to run your current Python file. Use :copen to show error list.

Answer 3

G'day,
Similar to karoberts answer, I prefer the more direct:
:map <F9> :!python %<CR>
If my script is creating some output I also like to capture it in a temp file and then autoread that files content into another buffer, e.g.
:map <F9> :!python % 2>&1 \| tee /tmp/results
I then set autoread by entering :set autoread and opening the results file in another buffer
:split /tmp/results<CR>
Then I can easily see the results of the run in the buffer that auto refreshes when the results file is updated by running the script under development.
HTH
cheers,

Answer 4

With new LUA api:
vim.api.nvim_create_user_command('Hello', 'echo "Hello World!"', {})
vim.api.nvim_create_user_command('HelloLua', function ()
print('Hello LUA!')
end, {})
NeoVIM API reference