Why does defining new match in Vim remove the previously defined one?

Question

To show trailing whitespace in Vim, I use the following:

highlight whitespaceEOL term=reverse ctermbg=Grey guibg=Grey
match whitespaceEOL /\s\+\(\%#\)\@!$/

When I use the following match for long lines, the first match is lost:

augroup longLines
    autocmd! filetype zsh,sh,python,vim,c,cpp :match ColorColumn /\%>80v.\+/
augroup END 

Why is that happening?

Answer 1

:match only matches one pattern at a time. :2match and :3match exist for exactly this reason. Try this:

2match whitespaceEOL /\s\+$/
3match ColorColumn /\%>80v.\+/

Alternatively, you can implement this as syntax. Try this:

syntax match whitespaceEOL /\s\+$/
syntax match ColorColumn /\%>80v.\+/