15 lines
310 B
Text
15 lines
310 B
Text
null → null
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() → null
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(null? 3) → #f
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(!null? 4) → #t
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(null? null) → #t
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;; careful - null is not false :
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(if null 'OUI 'NON) → OUI
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;; usual usage : recursion on lists until (null? list)
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(define (f list)
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(when (!null? list)
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(write (first list)) (f (rest list))))
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(f '( a b c)) → a b c
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