Converting an old Clipper app

[Silvio.Falconi]

I must ocnverte these lines from old clipper
someone can help me please (I use cdx tag)

or->(dbCreateIndex("orario.$$1", ;
"MA->prec + DO->punti", {|| ;
(MA->(dbGoto(OR->materia)), ;
DO->(dbGoto(OR->prof)), MA->prec + ;
DO->punti + eval({|| (DevPos(14, 14), iif(!EOF(), ;
DevOut(Replicate("²", RecNo() * 51 / LastRec())), Nil), ;
"")}))}))

OR->(dbCreateIndex("orario.$$2", ;
"OR->classe + str( OR->gruppo, 3 ) + OR->gg_ora", ;
{|| OR->classe + Str(OR->gruppo, 3) + OR->gg_ora + ;
eval({|| (DevPos(14, 14), iif(!EOF(), DevOut(Replicate("²", ;
RecNo() * 51 / LastRec())), Nil), "")})}))

[James Bott]

Wow, that is some really complex stuff. It gives me a headache just to look at it.

What is the problem? Have you tried compiling it and it generates errors? If so, what are the errors?

Something else?

[Silvio.Falconi]

James,
I wrote on private email to you for this problem

[mercurial]

These calls create indexes and use a "trick" to show a progress bar, that is calculated and shown for each record, together with cursor positioning. I don't know which Clipper version you were using with that code but [x]Harbour can call a callback function every x indexed records. In this way you'll use a supported, official, less invasive tecnique.
Please open the file std.ch from [x]Harbour include directory and search for INDEX ON and you will find that INDEX ON.... is split into ordCondSet() and ordCreate() function calls. With the first call you can specify filters and also the callback function. It seems to me that the progress bar is 50 chars wide... with the new functions you will move the cursor, calculate and display the progress bar only 50 times...

You say that you use the cdx tag. But it seems to me that you are not actually using multitag (one file with multiple indexes inside) but only one file one index in cdx format. But I may be wrong.

orario.$$2 seems "easy".

What puzzle me a bit is orario.$$1...

Code: Select all | Expand

or->(
   dbCreateIndex("orario.$$1",           // for each record in OR(ario)
      "MA->prec + DO->punti",
      {|| (MA->(dbGoto(OR->materia)), ;  // move record in workarea MA(terie)
           DO->(dbGoto(OR->prof)),       // move record in workarea DO(centi)
           MA->prec + DO->punti + ;      // create the string to use as index
           eval( {||""}) ;               // eval always returns ""
           )  }  )  )
 

Probably I'd use a SET RELATION and not the dbGoto... well, actually the dbGoto is the equivalent of the SET RELATION... but SET RELATION moves the pointers in other workareas automatically... but you need to set them up every time you open the files... so PROs and CONS...

Anyway, I think that this is a smart way to avoid using a new table for setting the relations between the three records...!