-notation < "↓ \ensp a" with precedence 60 for @{ 'downarrow $a }.
-notation > "↓ a" with precedence 60 for @{ 'downarrow $a }.
-
-notation "hvbox(U break ↓ V)" non associative with precedence 60 for @{ 'fintersects $U $V }.
-
-notation "↑a" with precedence 60 for @{ 'uparrow $a }.
-
-notation "hvbox(a break ↑ b)" with precedence 60 for @{ 'funion $a $b }.
-