[Oberon] Negative integer literals in Oberon

[dave at brownsmeet.com]

Yes, that seems good.

Personally I am surprised there is not more support in compilers (of all 
languages) for generating run time integer overflow checking code.

In my Pascal days I got into the habit of using subranges rather than 
INTEGER pretty much everywhere, and caught quite a few mistakes. It 
seems highly likely that I have not stopped making such mistakes since 
using languages without integer range checking :-(.

Re suffix characters and the number of integer types - it seems to me 
that we should solve for more sizes - there is a lot of data that is 
composed of sequences of 8 bits, and 16 bit data exists too. If our 
solution involves suffices at all, then I would like to see HEX suffixes 
available for all 4 sizes.

Cheers -- Dave.


On 2020-05-02 12:59, Joerg wrote:
> Dave
> 
> Let’s assume we are on a 64bit CPU and we have two integer types:
> INTEGER (32bit) and LONGINT (64bit)
> 
> In my point of view, you would need two value cast operators H and L
> to cover those cases.
> 
> But in additiion to the H and L thingy, the compiler might make a
> difference between
> SHORT(long) and
> SYSTEM.VAL(INTEGER, long)
> 
> SHORT could generate a runtime error.
> SYSTEM.VAL most probably not as it is low level and most compilers
> implement this just as
>    long MOD 100000000L
> 
> br
> Jörg
/oberon