Doru Many thanks. I knew it must be something simple. I was nearly there, because I had tried 'negated' as an alternative to 'not'. You may regret the invitation in your last line. The documentation is rather sparse, so there may well be more questions. I shall always try to solve it myself first, of course. Thanks also for the speedy answer - on a Saturday afternoon too! Peter
_____ From: Pharo-users [mailto:pharo-users-boun...@lists.pharo.org] On Behalf Of Tudor Girba Sent: 22 February 2014 16:38 To: Any question about pharo is welcome Subject: Re: [Pharo-users] Moose: Problem in Petit Parser Hi, For Moose related questions, there exists a dedicated mailing list: http://www.moosetechnology.org/about/contact Related to your problem, "not" does consume the input. You want to use "negate", which is implemented as: PPParser>>negate "Answer a new parser consumes any input token but the receiver." ^ self not , #any asParser ==> #second Keep the questions flowing :) Cheers, Doru On Sat, Feb 22, 2014 at 5:25 PM, PBK Research <pe...@pbkresearch.co.uk> wrote: Hello All Not sure whether this is the right forum for this question - please excuse and point me in the right direction if I'm wrong. I have been playing with Moose 4.8, downloaded last October, mainly because I am interested in PetitParser. I have been constructing fairly trivial parsers to get to understand the system. I took as an example a typical HTML tag, i.e. any text enclosed in angle brackets <>. My first attempt was: ($< asParser, $> asParser not star, $> asParser). This seemed to send the parser into a loop, except in the case where there was no text between the brackets. Floundering around, I tried: ($< asParser, (PPPredicateObjectParser anyExceptAnyOf: '>') star, $> asParser). This worked as expected, but I was not happy with the apparent clumsiness of the middle term. So I tried: ($< asParser, (PPPredicateObjectParser char: $>) not star, $> asParser). This again sent the parser into a loop. It looks as though I have some fundamental misunderstanding of the function of 'not' in a parser, or else it is not working as specified. Could someone kindly explain to an inquisitive idiot what is going wrong? Many thanks in advance Peter Kenny -- www.tudorgirba.com "Every thing has its own flow"
