Hi, yes, this seems to be an even better solution.
Best Regards, Gy�rgy ============================================ dr. Gy�rgy R�THY Ericsson Communications Systems Hungary Lim. Conformance Center tel.: +36 1 437-7006; fax: +36 1 437-7767 mobile: +36 30 297-7862 e-mail: [EMAIL PROTECTED] intranet: http://www.r.eth.ericsson.se/~ethgry ============================================ >-----Original Message----- >From: Egon Andersen, Talura [mailto:[EMAIL PROTECTED]] >Sent: Friday, January 18, 2002 1:33 PM >To: [EMAIL PROTECTED] >Subject: Re: [ASN.1] Is this a legal SEQUENCE ? > > >"Gyorgy Rethy (ETH)" wrote: >> >> Hi, >> >> looking at the ASN.1 2002 draft there is an addition (the >last alternative of ComponentTypeLists) related to this issue; >the current bnf looks like this (if there is no newer version): >> SequenceType ::= >> SEQUENCE "{" "}" | >> SEQUENCE "{" ExtensionAndException > OptionalExtensionMarker "}" | >> SEQUENCE "{" ComponentTypeLists "}" >> ExtensionAndException ::= "..." | "..." ExceptionSpec >> OptionalExtensionMarker ::= "," "..." | empty >> ComponentTypeLists ::= RootComponentTypeList | >> RootComponentTypeList "," >ExtensionAndException ExtensionAdditions OptionalExtensionMarker | >> RootComponentTypeList "," >ExtensionAndException ExtensionAdditions ExtensionEndMarker "," >> RootComponentTypeList | >> ExtensionAndException >ExtensionAdditions ExtensionEndMarker "," RootComponentTypeList | >> ExtensionAndException >ExtensionAdditions ExtensionEndMarker >> >> RootComponentTypeList ::= ComponentTypeList >> ExtensionEndMarker ::= "," "..." >> ExtensionAdditions ::= "," ExtensionAdditionList | empty >> etc. >> >> According to this bnf the type definition below is illegal, >because the ExtensionEndMarker does not have an "empty" path. >But I think, a second extension marker is not really necessary >in this case and the last alternative of ComponentTypeLists >could be changed to (it would make this alternative to "rhyme" >with the second altenative of SequenceType): >> >> ExtensionAndException >ExtensionAdditions OptionalExtensionMarker >> >> With this change in the bnf the quoted type would become legal. >> >> Best Regards, Gy�rgy >> > >It would be better to use: > >ExtensionAndException "," ExtensionAdditionList OptionalExtensionMarker > >because the other solutions will give multiple ways through the BNF. > >Best regards >Egon Andersen >-- >* Talura ApS * Phone: +45 43 52 50 00 * >* Baldersh�j 24 B * mailto:[EMAIL PROTECTED] * >* DK-2635 Ish�j * http://www.talura.dk * >
