An `after/plugin` function for Tabular.vim to allow PCRE (using eregex.vim)

tabular_after.vim

if exists(':E2v')
    function! AlignByRE() range
        let range  = a:firstline . ',' . a:lastline
        let cmd    = range
        let re = input('Enter PCRE to align by: ')
        if re == ""
            " Run empty to use previous pattern
            let cmd .= 'Tabularize'
            execute cmd
        else
            let vim_re  = E2v(re)
            let cmd    .= 'Tabularize/' . vim_re
        endif
        execute cmd
    endfunction
    nnoremap <leader>A :call AlignByRE()<CR>
    vnoremap <leader>A :call AlignByRE()<CR>
endif