In Haskell, bounding is achieved by requiring types to belong to a type class; thus the same function has the type E q α ⇒ α → → B o o l {\displaystyle {\scriptstyle Eq\,\alpha \,\Rightarrow \alpha \,\rightarrow \left\rightarrow Bool}} in Haskell.
在Haskell中，限定是通过要求类型属于某个type class，因此同样的函数在Haskell中可写为： E q α ⇒ α →  → B o o l {\displaystyle {\scriptstyle Eq\,\alpha \,\Rightarrow \alpha \,\rightarrow \left\rightarrow Bool}} 。