Vim key mapping not working correctly for Ctrl key not working

Question

I'm trying to do the following mapping noremap <ESC>:<C-w>l <leader>l, or noremap <ESC><C-w>l <leader>l, or some mapping that accomplishes the same effect, to make switching between window splits 100x easier. The issue is that I get an E20: Mark not set message. What am I doing wrong? Is this a bug? Or is it just not possible? I've got mappings to split the window, but I can't seem to get this to work.

Answer 1

I'm stupid... I've got the arguments in the wrong order.