[Oberon] Easter eggs in Oberon
August Karlstrom
fusionfile at gmail.com
Mon Apr 13 20:49:19 CEST 2020
On 2020-04-13 17:36, Joerg wrote:
> The word „numeric type“ is not clearly defined in the report.
>
> Eg. is BYTE part of the numeric types?
BYTE is defined as "the integers between 0 and 255" and integers are
numeric, so the answer must be yes.
> Or is INTEGER part of the numeric type?
It has to be, otherwise you would not able to calculate anything with
integers.
> If it was you sould be able to write i := i / 3; (as / is defined on numeric types)...
No, because "The operators +, −, *, and / apply to operands of numeric
types. Both operands must be of the same type, which is also the type of
the result." The result of i / 3 is not an integer unless i is a
multiple of three. Therefor it applies to operands of type REAL.
> The Oberon report leaves some room for interpretation... (especially for corner cases)
>
> b := -2; is equivalent to b := 254;
It may give the same result on one implementation but it is still
undefined; again the Oberon report says that BYTE is "the integers
between 0 and 255," not "the integers between -128 and 127."
-- August
More information about the Oberon
mailing list