Re: Is this use of BASE kosher?

Owen Rees (
Tue, 1 Aug 95 12:44:51 EDT

"Daniel W. Connolly" <> writes:
> In message <>, Owen Rees writes:
> > (I am happy with either enco
> >ded or not encoded, but absolutely opposed to encoding being optional - that o
> >ld ambiguity argument again.)
> I think it's folly to say that we've found all the characters that
> might be disallowed in any context in which URLs will be used, and
> hence to say that any URL has exactly one unambiguous "spelling."
> I think that http://a and http://%61 are exactly the same URL.

Doing more encoding of text already known to be a URL is not the problem I am concerned about. What I want to be certain about is whether a piece of text is a URL (therefore encoded already) or is a something that can be turned into a URL by applying the encoding. I think that the most important point is whether or not the '%' characters have been encoded - this must be done once and only once.

I have two files "a.html" and "%61.html". Given the right base, the URL "%61.html" refers to the file "a.html" and not to the file "%61.html". The URL "%2561.html" refers to the file "%61.html". From the text "%61.html" alone, it is not possible to determine which file it refers to; the context in which it occurs must unambiguously define whether or not encoding has been done.

Current practice seems to be that
<A HREF="%2562.html#%61">%2562.html#%61</A> refers to
<A NAME="%61">This is %61 in %62.html</A> and not to
<A NAME="a">This is a in %62.html</A>.
Neither anchor names not fragment identifiers behave as if encoded. If the same text is used the link works - this property would be preserved (I think!) if both were interpreted as encoded, thus adopting the RFC1808 fragment syntax without breaking existing links.

Owen Rees
<>, <URL:>
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