vim - how do I set a shortcut?

Question

I'm trying to follow the instructions for configuring NeoComplete

The config example is this:

inoremap <expr><C-l>     neocomplete#complete_common_string()

I'm assuming this means, press Ctrl-L to accept the first completion. It doesn't work.

Can someone explain the <expr><Cl> bit?

Answer 1

if you used <expr> mapping, it means, the string returned by given expression will be {rhs} mapping.

Eg you have a function return a string abc , then with nnoremap <expr> , your mapping will do same in normal mode pressing abc