How does the compiler handle case statements?

Question

The documentation in the case reports, it says:

Each value represented by caseList must be unique in the case of an expression;

And an example is shown,

case I of
  1..5: Caption := 'Low';
  6..9: Caption := 'High';
  0, 10..99: Caption := 'Out of range';
else
  Caption := ;
end

equivalent to a nested conditional:

if I in [1..5] then
  Caption := 'Low';
else if I in [6..10] then
  Caption := 'High';
else if (I = 0) or (I in [10..99]) then
  Caption := 'Out of range'
else
  Caption := ;

So, the first quote suggests that it is treated as a set (read the comments here at least one person with me on this).

Now i know the part

where selectorExpression is any ordinal expression less than 32 bits

contrary to a number of properties, as mentioned it at sets:

The base type can have no more than 256 possible values, and their orders must be between 0 and 255

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Answer 1

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const
  NEW_CUSTOMER = 0;
  EDIT_CUSTOMER = 1;
  ...
  CANCEL_OPERATION = 0;

case UserAction of
  NEW_CUSTOMER : ...;
  EDIT_CUSTOMER : ...;
  ...
  CANCEL_OPERATION : ...; { Compiler error is very helpful. }
end;

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Answer 2

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