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>Could the responsible parties please answer these questions, and post
>the questions and answers to the scheme mailing list? Thanks.
Maybe that should be "irresponsible parties". I guess someone has to take
the rap, so here are my excuses.
1) The report mentions two procedures (close-input-port <port>) and
(close-output-port <port>). I don't see why it is necessary to
have two procedures to close ports. Wouldn't it be sufficient
to have something like "close-port" that can be applied to both
types of ports?
Yes, and I would not be surprised if most Scheme implementations do it
that way internally. OPEN-INPUT-FILE and OPEN-OUTPUT-FILE need to be
distinct, and I guess it seemed more symmetric for them to have distinct
2) What is the exact difference between (write-char <char>) and
(display <char>)? "write-char" seems to be redundant. Is "display"
supposed to terminate its output by a space or newline or something
Chris Hanson noted the historical fact that DISPLAY originally acted like
WRITE on characters, so WRITE-CHAR was once necessary for that reason. He
noted also that DISPLAY, being generic, is likely to be much less efficient
than WRITE-CHAR. Kent Dybvig pointed out that characters are not guaranteed
to be distinct from other data types, say small integers or strings of one
character, so WRITE-CHAR is the only portable way you can write a character
itself as opposed to some representation of the character. Thus WRITE-CHAR