10 lines
350 B
Text
10 lines
350 B
Text
procedure main()
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nulltest("a",a) # unassigned variables are null by default
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nulltest("b",b := &null) # explicit assignment is possible
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nulltest("c",c := "anything")
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nulltest("c",c := &null) # varibables can't be undefined
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end
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procedure nulltest(name,var)
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return write(name, if /var then " is" else " is not"," null.")
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end
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