Reserved Notation "a ~~> b" (at level 70, right associativity).
Reserved Notation "F ~~~> G" (at level 70, right associativity).
Reserved Notation "F <~~~> G" (at level 70, right associativity).
+Reserved Notation "F <~~⊗~~> G" (at level 70, right associativity).
Reserved Notation "a ⊗ b" (at level 40).
Reserved Notation "a ⊗⊗ b" (at level 40).
Reserved Notation "a ⊕ b" (at level 40).