25 lines
656 B
Common Lisp
25 lines
656 B
Common Lisp
(lib 'types)
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(lib 'struct)
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(struct T (integer:x)) ;; super class
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(struct S T (integer:y)) ;; sub class
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(struct K (T:box)) ;; container class, box must be of type T, or derived
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(define k-source (K (S 33 42)))
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(define k-copy (copy k-source))
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k-source
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→ #<K> (#<S> (33 42)) ;; new container, with a S in box
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k-copy
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→ #<K> (#<S> (33 42)) ;; copied S type
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(set-S-y! (K-box k-source) 666) ;; modify k-source.box.y
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k-source
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→ #<K> (#<S> (33 666)) ;; modified
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k-copy
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→ #<K> (#<S> (33 42)) ;; unmodified
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(K "string-inside") ;; trying to put a string in the container box
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😡 error: T : type-check failure : string-inside → 'K:box'
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