DITA project

> On 12 mrt. 2015, at 20:33, France Baril <france.baril at architextus.com> wrote: > > Hi, > > I'm working on a new DITA project. The DITA standard is used for technical documentation. It creates XML models with inheritance by using @class="ancestor parent child". If the child should behave like it's ancestor the XSL would say: > <template match="contains(@class, 'ancestor')"> ... </template> > > The advantage is that the model can evolve and when new elements are added, you only need to code transformations for the differences. > > I am trying to figure out if I can use type switching with contains in attribute. Search gets me no syntax for something like this: > > typeswitch ($node) > case attribute(contains(class, 'ancestor')) > > Maybe I should register to the xquery group to get an answer, but since I'm already here, I though I should ask, and maybe there is a BaseX specific option. I mean other that an unmanageable number of 'if then else' statements. > > Thanks! > > > > -- > France Baril > Architecte documentaire / Documentation architect > france.baril at architextus.com

On Thu, Mar 12, 2015 at 10:45 PM, Marc van Grootel <marc.van.grootel at gmail.com> wrote: > > Hi France, > > Typeswitch is not the right tool for this. > > From the spec: > > [74] TypeswitchExpr ::= "typeswitch" "(" Expr ")" CaseClause+ "default" ("$" VarName)? "return" ExprSingle > [75] CaseClause ::= "case" ("$" VarName "as")? SequenceTypeUnion "return" ExprSingle > [76] SequenceTypeUnion ::= SequenceType ("|" SequenceType)* > > > As the name implies it is meant for checking (sequence) types and not for arbitrary XPath expressions. > > Also, using contains isn't watertight as contains('foobar','foo') would match as well. I would probably use a function like this > > declare function in-class($node as element(), $class as xs:string) as xs:boolean { > $class = tokenize($node/@class,'\s+') > } > > Do check performance in your situation. In case you need to do many checks on the same class attribute you may want to bind the tokenized value list with a let instead of using this function. > > I also remember that Michael Kay is looking into improving on exactly this use case. But that doesn't help you now. > > Cheers, > --Marc > > On 12 mrt. 2015, at 20:33, France Baril <france.baril at architextus.com> wrote: > > Hi, > > I'm working on a new DITA project. The DITA standard is used for technical documentation. It creates XML models with inheritance by using @class="ancestor parent child". If the child should behave like it's ancestor the XSL would say: > <template match="contains(@class, 'ancestor')"> ... </template> > > The advantage is that the model can evolve and when new elements are added, you only need to code transformations for the differences. > > I am trying to figure out if I can use type switching with contains in attribute. Search gets me no syntax for something like this: > > typeswitch ($node) > case attribute(contains(class, 'ancestor')) > > Maybe I should register to the xquery group to get an answer, but since I'm already here, I though I should ask, and maybe there is a BaseX specific option. I mean other that an unmanageable number of 'if then else' statements. > > Thanks! > > > > -- > France Baril > Architecte documentaire / Documentation architect > france.baril at architextus.com

On Fri, Mar 13, 2015 at 4:52 AM, Christian Grün <christian.gruen at gmail.com> wrote: > A little addition: XQuery 3.1 provides the function contains-token to > request single values of attributes. It basically does what Marc > proposed [1]: > > let $input := <a class='ancestor field'/> > let $class := $input/@class > return if(contains-token($class, 'ancestor')) then ( > 1 > ) else if(contains-token($class, 'descendant')) then ( > 2 > ) else ( > 0 > ) > > This is one more way to do it: > > let $input := <a class='ancestor field'/> > let $tokens := map:merge( > tokenize($input/@class, '\s+') ! map { .: true() } > ) > return if($tokens?ancestor) then ( > 1 > ) else if($tokens?descendant) then ( > 2 > ) else ( > 0 > ) > > Best, > Christian > > [1] http://docs.basex.org/wiki/XQuery_3.1#fn:contains-token > > > > On Thu, Mar 12, 2015 at 10:45 PM, Marc van Grootel > <marc.van.grootel at gmail.com> wrote: > > > > Hi France, > > > > Typeswitch is not the right tool for this. > > > > From the spec: > > > > [74] TypeswitchExpr ::= "typeswitch" "(" Expr ")" CaseClause+ > "default" ("$" VarName)? "return" ExprSingle > > [75] CaseClause ::= "case" ("$" VarName "as")? SequenceTypeUnion > "return" ExprSingle > > [76] SequenceTypeUnion ::= SequenceType ("|" SequenceType)* > > > > > > As the name implies it is meant for checking (sequence) types and not > for arbitrary XPath expressions. > > > > Also, using contains isn't watertight as contains('foobar','foo') would > match as well. I would probably use a function like this > > > > declare function in-class($node as element(), $class as xs:string) as > xs:boolean { > > $class = tokenize($node/@class,'\s+') > > } > > > > Do check performance in your situation. In case you need to do many > checks on the same class attribute you may want to bind the tokenized value > list with a let instead of using this function. > > > > I also remember that Michael Kay is looking into improving on exactly > this use case. But that doesn't help you now. > > > > Cheers, > > --Marc > > > > On 12 mrt. 2015, at 20:33, France Baril <france.baril at architextus.com> > wrote: > > > > Hi, > > > > I'm working on a new DITA project. The DITA standard is used for > technical documentation. It creates XML models with inheritance by using > @class="ancestor parent child". If the child should behave like it's > ancestor the XSL would say: > > <template match="contains(@class, 'ancestor')"> ... </template> > > > > The advantage is that the model can evolve and when new elements are > added, you only need to code transformations for the differences. > > > > I am trying to figure out if I can use type switching with contains in > attribute. Search gets me no syntax for something like this: > > > > typeswitch ($node) > > case attribute(contains(class, 'ancestor')) > > > > Maybe I should register to the xquery group to get an answer, but since > I'm already here, I though I should ask, and maybe there is a BaseX > specific option. I mean other that an unmanageable number of 'if then else' > statements. > > > > Thanks! > > > > > > > > -- > > France Baril > > Architecte documentaire / Documentation architect > > france.baril at architextus.com >

On Fri, Mar 13, 2015 at 12:01 PM, Marc van Grootel < marc.van.grootel at gmail.com> wrote: > Hi France, > > If you really need multi-branching if then else the language doesnt > require increasing indentation. > > if (cond1) > then expr1 > else if (cond2) > then expr2 > else expr3 > > In my opinion this is just as good as using switch, i've seen examples > like this even in the spec. Of course readability suffers if there's a lot > going on in the expressions such as complete flwor expressions but that's > just a matter of breaking up the code in smaller (re-usable) > pieces/functions. > > Breaking up / refactoring your logic to avoid massive if then else or > switch constructs is advisable anyway. But I don't know how your code looks > so I cannot say. > > hth > --Marc