🚀 go-pugleaf

In article <3179@cognos.UUCP> keithc@cognos.UUCP (Keith Campbell) writes:
>In article <INFO-M2%88060616534629@UCF1VM> Nathan Bohlmann writes:
>>type-casting can be accomplished as follows:
>>     If Type1 is of type CARDINAL then to get an value of integer
>>     type all you need to do is say INTEGER(Type1).  That's all
>>     there is to it.
>>There are several other extensions which escape me at the moment...
>
>I believe that the feature to which you refer, is NOT an extension,
>but rather has always been in the definition of modula2.  Has some
>standardization effort removed it?

In Wirth's Modula-2, "INTEGER(65535)" has the value -1 (on a two's
complement machine with 16-bit INTEGERs).  In BSI/ISO Modula-2, it is an 
overflow error.  In the first case, the type transfer is not meaning
preserving, but bit-pattern preserving.   In the second case, the
opposite is true.  The above quote does not explain which option
is implemented by the compiler in question.

I think the BSI approach is superior.  BSI also has defined a mechanism
for bit-pattern preserving (non-meaning preserving) type transfers.  It
is a pseudo-function that must be imported from SYSTEM and whose name
currently escapes me.  So BSI's langauge has the same (in fact, more)
functionality but with different syntax.




-- 
Alan Lovejoy; alan@pdn; 813-530-8241; Paradyne Corporation: Largo, Florida.
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