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Re: arithmetic issues
Aubrey Jaffer <agj@xxxxxxxxxxxx> writes:
> In R5RS the eof-object has no read-syntax. If it did, then calls to
> READ would be unable to distinguish between an actual end of file
> and an eof object written in a file.
This reason does not apply to NaN. It's not used to signal the end
> Okay, how about a library function:
> (define NaN (lambda()
What advantage it has over a literal syntax? A NaN must have a literal
syntax anyway for output. So why not use it for input too? All Scheme
values which have a defined output syntax use it also for input.
> So your code is clear and readable, and yet you don't have a
> read/write syntax that makes it unclear whether read is failing or
> just reading an error.
Read should never fail on NaN. If it's present in the stream provided
for reading, it's meant to be read.
__("< Marcin Kowalczyk