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Postings from September 2001
> Uri Guttman > > we are planning automatic over/underflow to bigfloat. so there is no > > need for traps. they could be provided at the time of the > > conversion to big*. > > OK. But will Perl support signaling and non-signaling NANs? I don't think we should go for automatic overflow/underflow between float and bigfloat. The float exception (overflow, underflow, inexact, divide zero, ...) is very difficult to handle. Using Unix signal is expensive and very platform-specific (lots of ucontext issues). Since C language does not support floating-point signal, we may use some assembly code to handle it, it will be porting nightmare. Since most of floating-point assumes IEEE-semantics, taking automatic float/bigfloat will change this assumption significantly. It may a lot of code and algorithm. I think it is safer just to provide a BigDecimal class for developers to use, and keep the basic float semantics (close to 64-bit IEEE-754 if possible). HongThread Previous | Thread Next