- From: C. M. Sperberg-McQueen <cmsmcq@blackmesatech.com>
- Date: Sat, 05 Feb 2022 06:55:58 -0700
- To: Bethan Tovey-Walsh <accounts@bethan.wales>
- Cc: Norm Tovey-Walsh <norm@saxonica.com>, Dave Pawson <dave.pawson@gmail.com>, public-ixml@w3.org
Bethan Tovey-Walsh writes: > Okay, that’s all fair. ... > ... My only slight disagreement is that, if we’re talking > specifically of an ixml grammar parser, failure to recognise the input > must be an error. If the input string isn’t recognised, it isn’t a > valid ixml grammar and it can’t subsequently be used as the “ixml > grammar” input to an ixml input parser. > Does that make sense? I think it does. (And I think the reasons that 'error' makes sense here and not in the case of the input string not being a sentence are (1) that the ixml spec does define conformance rules for input grammars, and (2) that a user who specifies an input grammar is implicitly warranting that it's a conforming gramar. Note that I think point (2) has a slighty subtle consequence. It means, I think, that if the file "bad.ixml" contains the non-grammar S ::= "hi mom". then whether it is "in error" in the narrow sense seems to depend on how the processor is invoked. If I invoke an ixml processor asking to parse the input "hey, bro!" against the grammar in bad.ixml, the processor will discover that bad.ixml is not a conforming grammar, and it seems to me to make sense tosa that it is "in error". If on the other hand I invoke the ixml processor asking it to parse bad.ixml against the ixml specification grammar, I am making no implicit claims that bad.ixml is a conforming grammar and so I would be uncomfortable saying that in that case the file bad.ixml is "in error". Michael -- C. M. Sperberg-McQueen Black Mesa Technologies LLC http://blackmesatech.com
Received on Saturday, 5 February 2022 13:56:20 UTC