[cdr-discuss] Re: [RfC] WITH-READTABLE-ITERATOR
abadichi at bezeqint.net
Thu Oct 2 23:41:46 UTC 2008
"Tobias C. Rittweiler" <tcr at freebits.de>
> Ariel Badichi proposed coalescing a generator's fourth return value
> (indicating if the returned character is a dispatch macro character)
> with its first return value (indicating if the generator is
An example of the results returned by the generator, according to my
proposal, would be:
:MACRO-DISPATCH-CHAR, #\#, #<FN>, (...)
T, #\#, #<FN>, T, (...)
I find the former more intelligible. I also find, however, that Stephen
Compall has made a strong argument in support of the interface proposed
in the draft. If I understand him correctly, it is that there are (and
always will be) just two kinds of macro characters, dispatching and
non-dispatching, and that by using a boolean to discriminate between
them, we save the user the work of mapping them herself in many cases.
In light of this argument, I am ready to cope with the unpleasant
consequences of the draft's proposal.
> Exceptional Situations ......................
> Signals an error of type `program-error' if a MACRO-CHAR-TYPE is
> supplied that is not recognized by the implementation.
The outcome of having a non-symbol given as a generator name is not
specified. Might it also be the signaling of a `program-error'
condition, or should it remain unspecified?
The outcome of having a non-readtable given for iteration is not
specified. Should it be the signaling of an error, or should it remain
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