+ method remainder : signal_type -> signal_type
+ method gt : signal_type -> signal_type
+ method lt : signal_type -> signal_type
+ method geq : signal_type -> signal_type
+ method leq : signal_type -> signal_type
+ method eq : signal_type -> signal_type
+ method neq : signal_type -> signal_type
+ method shl : signal_type -> signal_type
+ method shr : signal_type -> signal_type
+ method max : signal_type -> signal_type
+ method min : signal_type -> signal_type