Conditional structures: Difference between revisions
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→case without a default: the error discussed isn’t syntactic
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);</syntaxhighlight>
====case expressions====
Using the same example above, we assume that the
<syntaxhighlight lang="ada">Result := (case Op is
Add => A + B,
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</syntaxhighlight>
Note: some websites (particularly [https://www.radford.edu/nokie/classes/320/abe/operators.html#:~:text=if%20and%20case-,Examples%3A,1%2C%20others%20%3D%3E%200)%3B this one]) contain a different variant of a case expression (<syntaxhighlight lang="ada">case Op of...</syntaxhighlight>). The Ada Reference Manual indicates this is incorrect, and we use the [http://www.ada-auth.org/standards/12rm/html/RM-4-5-7.html formal version] here.
===case with a default alternative===
<syntaxhighlight lang="ada">type Days is (Monday, Tuesday, Wednesday, Thursday, Friday, Saturday, Sunday);
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===case without a default===
When there is no '''when others''' clause, the compiler will complain about any uncovered alternative. This defends against a common reason for bugs in other languages.
I.e., the following code is
<syntaxhighlight lang="ada">case Today is
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end case;</syntaxhighlight>
The
<syntaxhighlight lang="ada">case Today is
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