18 lines
348 B
Plaintext
18 lines
348 B
Plaintext
type nullableString(object o)
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return string(o) or o=NULL
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end type
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nullableString s
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s = "hello"
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s = NULL
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--s = 1 -- error
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--s = {1,2,3} -- error
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type nullableSequence(object o)
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return sequence(o) or o=NULL
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end type
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nullableSequence q
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q = {1,2,3}
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q = "string" -- fine (strings are a subset of sequences)
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q = NULL
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--q = 1 -- error
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