我在 Haskell 中实现了一个计算器来复习语言,但是当我希望它进入无限循环直到用户输入时,我在 main 中遇到了障碍q
。这是我的主要内容,如果您看到我做错了什么并且生病也发布我的错误,请告诉我
error: No instances for (Floating (IO a0), Read (IO a0))
arising from a use of `compute'
Possible fix:
add instance declarations for (Floating (IO a0), Read (IO a0))
In a stmt of a 'do' block: compute e
In the expression:
do { compute e;
evaluate_input }
In an equation for `evaluate_expression':
evaluate_expression e
= do { compute e;
evaluate_input }