function! Sc(char)
    let closing = {'(': ')', '[': ']', '{': '}', '<': '>', '"': '"', "'": "'"}
    
    if has_key(closing, a:char)
        let line = getline('.')
        let col = col('.') - 1
        let before = col > 0 ? line[col-1] : ''
        let after = col < len(line) ? line[col] : ''
        if before =~ '\w' && after =~ '\w'
            return a:char
        endif
        if (a:char == '"' || a:char == "'") && before == a:char
            return a:char
        endif
        if after == closing[a:char]
            return "\<Right>"
        endif
        return a:char . closing[a:char] . "\<Left>"
    endif
    
    return a:char
endfunction

inoremap ( <C-R>=Sc('(')<CR>
inoremap [ <C-R>=Sc('[')<CR>
inoremap { <C-R>=Sc('{')<CR>
inoremap < <C-R>=Sc('<')<CR>
inoremap " <C-R>=Sc('"')<CR>
inoremap ' <C-R>=Sc("'")<CR>