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Re: Issues with Unicode

This page is part of the web mail archives of SRFI 75 from before July 7th, 2015. The new archives for SRFI 75 contain all messages, not just those from before July 7th, 2015.

Sebastian Egner scripsit:

> One could start with a SRFI for immutable strings as an add-on
> library---in the hope that the Scheme community will pick it up
> as the primary string type in the distant future.

Actually, getting immutable strings into R6RS would be trivial in
terms of the document:  simply replace the sentence

	String-set! stores CHAR in element K of STRING and returns an
	unspecified value.

in 6.3.5 with the following:

	String-set! returns a string whose elements the same (in the
	sense of eqv?) as those in STRING, with the exception of element
	K, which is instead the same as CHAR.  String-set! may or may
	not return a string which is the same as STRING, but must not
	side-effect STRING.

> People might argue that the primitive strings of R5RS are much
> more efficient than any advanced string type, e.g. ropes. 

That's unequivocally false.  They are faster for string-ref! and
string-set!, may or may not be faster for string-length, and are almost
surely slower for string-append.  and string-copy (for reasonably long
strings).  Unless you mean space-efficient, in which case simple arrays
obviously win.

>         http://portal.acm.org/citation.cfm?id=324139

This is behind a tollbooth, but
http://citeseer.ist.psu.edu/kaplan99purely.html is not.  It's always a
bad idea to cite portal.acm.org URLs on a public mailing list; not all
of us have ACM subscriptions.

My corporate data's a mess!                     John Cowan
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