| author | wenzelm | 
| Tue, 19 Jan 2021 13:48:53 +0100 | |
| changeset 73160 | aeba7bb4f4d4 | 
| parent 57804 | fcf966675478 | 
| permissions | -rw-r--r-- | 
| 47269 | 1  | 
theory MyList  | 
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imports Main  | 
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begin  | 
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datatype 'a list = Nil | Cons 'a "'a list"  | 
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fun app :: "'a list => 'a list => 'a list" where  | 
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"app Nil ys = ys" |  | 
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"app (Cons x xs) ys = Cons x (app xs ys)"  | 
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fun rev :: "'a list => 'a list" where  | 
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"rev Nil = Nil" |  | 
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"rev (Cons x xs) = app (rev xs) (Cons x Nil)"  | 
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value "rev(Cons True (Cons False Nil))"  | 
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(* a comment *)  | 
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end  |