问题
Is the identity function pre-defined in Scheme?
回答1:
Yes, but it's called values. Actually, that's usually used for multiple values, so it's a generalized multiple-arity identity function.
回答2:
In DrRacket I know that identity works. For example, (identity 12) => 12
来源：https://stackoverflow.com/questions/4969927/identity-function-in-scheme