gistfile1.txt

function! s:ParseMarkdown()
    let l:lines = getline(1,line("$"))
    let l:pages_lines = []
    let s:pages = []
    echo "Parsing..."
 
    for l:line in l:lines
        if l:line =~ '^#\+'
            if !empty(l:pages_lines)
                call add(s:pages, join(l:pages_lines, "\r\n"))
            endif
            
            let l:pages_lines = [ l:line ]
        elseif !empty(l:pages_lines)
            call add(l:pages_lines, l:line)
        endif
    endfor
    if !empty(l:pages_lines)
        call add(s:pages, join(l:pages_lines, "\r\n"))
    endif
    
    let s:max_page_number = len(s:pages)-1
endfunction