Compliance of numeric tower
FrankHB opened this issue · comments
The behavior on overlow is not specified. This allows compliant Scheme implementations to exist with de-facto C number semantics.
This seems problematic. C is allowed to crash on overflow. Is Scheme permissive to unexpected behavior and termination of the program in that case?
Hi, thanks for commenting! I am not an expert in the Scheme specification, so I am not entirely sure whether crashing on overflow is technically allowed in R7RS-Small. But please note that no C implementation commonly available today actually crashes on overflow, so it is a moot point. My plans were to have the Java semantics, which are better defined, and crash only on integer division by zero.
One important difference compared to C signed integer overflow, which C considers "undefined behavior". I would try to avoid that at any cost.
Sadly, I "temporarily" 🤣 stopped working on this project in 2020, and even though I still intend to resume it, I am not sure exactly when.
R7RS allows a program to crash on numeric overflow.
R6RS prescribes that implementation must raise an exception on overflow.