Highlight the current word... or using :let and <cword> together

Question

I'm trying to do this:

nnoremap <leader>* :let @/ ="<cword>"<cr><bar>:set hlsearch<cr>                                                   

but can't get the first bit to work

nnoremap <leader>* :let @/ ="<cword>"<cr>

I want to highlight the word under the cursor but not jump to the next match automatically (often this is useful if you have multiple files open and you want to highlight a function definition in another file where you are using the function in the first file.

I came up with the let bit after reading :h @/ and given :let is an ex command I thought I'd be able to use <cword>

I've got stuck with adding or removing the quotes - no quotes gives an error and quotes just makes it search for "<cword>" literally. Likewise I also tried single quotes.

I'd be open to other ways of achieving the same thing but I'd also like to get to the bottom of why this doesn't work

Answer 1

Managed to work it out after running into some difficulties using <cword> in a different mapping that was using / to search...

I ended up with this:

nnoremap <leader>* :let @/ = '\<'.expand("<cword>").'\>'<cr>:set hlsearch<cr>:echo<cr> 

This post showed me how to use cword in search.

This site told me that . is string concatenation

The \< and \> are vim regex for start and end of word so it stops it highlighting part of nohlsearch if you used the command on hlsearch

The echo at the end is just to clear the commandline.

When doing something a bit like this but more complicated I also got caught by the difference between single and double quotes.... basically use single quotes when you're doing regex!