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Re: output stream API

Michael Sperber <sperber@xxxxxxxxxxxxxxxxxxxxxxxxxxx> writes:

>> 6. It would be great if there were a mechanism specified for passing
>> additional arguments (options) between the levels. Learning from
>> other existing I/O libraries, it is a recurring problem that you
>> need to pass funny little hints (e.g. access permission flags) down
>> (and sometimes up) the protocol stack to do what you need to do. I
>> am not talking about arcane IOCTLs, but over simple things like
>> opening a file for writing with the right attributes to actually be
>> able to write to it (this is no joke, R5RS open-output-file does not
>> specify what happens if the file exists.)
> That's definitely true.  At the time of writing, I didn't have a good
> solution, so I stuck with using separate procedures for the common
> options.  (I really dislike keyword arguments for various reasons.)  I
> have a better idea now, and I'll try to do something about the issue
> with the next revision.

Having said that, note that I fully expect platform-specific options
to come up, as well as platform-specific methods for creating readers
and writers.  That's not inherently bad, given that the sets of
available options *are* platform-specific.  It would be nice to
standardize on those as well, but they don't fall in the purview of
this particular SRFI.

(The SML Basis actually has a fourth, OS-specific layer, with variants
for Unix and Windows.)

Cheers =8-} Mike
Friede, Völkerverständigung und überhaupt blabla