24 lines
648 B
Standard ML
24 lines
648 B
Standard ML
fun valid_date (d:int, m:string) = if (m="January" orelse
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m="March" orelse
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m="May" orelse
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m="July" orelse
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m="August" orelse
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m="October" orelse
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m="December") andalso
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d <= 31 andalso
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d >= 0 then
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true
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else if (m="April" orelse
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m="June" orelse
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m="September" orelse
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m="November") andalso
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d <= 30 andalso
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d >= 0 then
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true
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else if m="February" andalso
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d <= 28 andalso
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d >= 0
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then
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true
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else false
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