// comment x "y" z // block block ( // block-eol // x-before-line "x" (y // x-eol "x") y // y-eol "x1" "x2" // line "x3" "x4" "x5" // y-line "y" // y-eol "z" // z-eol ) // block-eol2 block1 ( ) block2 (x y z) block3 "w" ( ) // empty block block4 "x" () "y" // not a block block5 ("z" // also not a block // eof