Null object: Difference between revisions
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Walterpachl (talk | contribs) m (→{{header|ooRexx}}: upperclass -> uppercase :-)) |
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if a[i] == .nil then say "Item" i "is missing" |
if a[i] == .nil then say "Item" i "is missing" |
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</lang> |
</lang> |
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Uninitialized ooRexx variables do not evaluate to .nil, but rather the character string name of the variable (all |
Uninitialized ooRexx variables do not evaluate to .nil, but rather the character string name of the variable (all uppercase). The var() built-in function allows variable validity to be tested: |
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<lang ooRexx> |
<lang ooRexx> |
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if \var("INPUT") then say "Variable INPUT is not assigned". |
if \var("INPUT") then say "Variable INPUT is not assigned". |
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</lang> |
</lang> |
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=={{header|Oz}}== |
=={{header|Oz}}== |
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