2007/1/29, Jean-Francois Dockes <[EMAIL PROTECTED]>:
Mikkel Kamstrup Erlandsen writes: > 2007/1/29, Jean-Francois Dockes <[EMAIL PROTECTED]>: > > > > Mikkel Kamstrup Erlandsen writes: > > > Hi All, > > > > > > I put together a first take on formalizing an end user search language. > > > > > > http://wiki.freedesktop.org/wiki/WasabiUserSearchLanguage > > > > - Which of OR and AND has priority ? (does (A AND B OR C) mean > > ((A AND B) OR C) or (A AND (B OR C)) ? > > > I guess it is standard that AND takes precedence over OR, but maybe it makes > sense to reverse that in our case. Think of the case > type:audio hendrix OR beatles > > In this case I would assume the user wants "audio files matching hendrix or > beatles", and not "audio files matching hendrix, or anything that matches > beatles"... I think it is non-standard however...
Thinking more about this operator precedence issue... What about || type:music jimi hendrix or beatles If OR had precedence over AND that search would not yield the expected results... Maybe a solution would be to simple put selectors completely out of logical scope with words and phrases. Always just AND them on to the expression. That way the search: || type:music jimi hendrix or beatles filetype:mp3 or filetype:ogg would give what is *probably* wanted... A totally other approach would be to have AND take precedence and use "," to separate expressions that should be ANDed together. Example: || type:music, jimi hendrix or beatles || type:music, jimi hendrix or beatles, filetype:mp3 or filetype:ogg The last example translates to: (type:music) AND ((jimi AND hendrix) OR beatles) AND (filetype:mp3 OR filetype:ogg) I actually kinda like that. It keeps the conventional AND precedence and allows simple grouping of expressions. In our case, I think that you are right and that it makes more sense to
have OR take precedence, this has my vote.
Are you still of the same opinion? Cheers, Mikkel
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