SCClassLibrary/Common/Streams/Prewrite.sc

   1 Prewrite : FilterPattern {
   2         var <>dict, <>levels;
   3         *new { arg pattern, dict, levels=1;
   4                 ^super.new(pattern).dict_(dict).levels_(levels)
   5         }
   6         storeArgs { ^[ pattern, dict, levels ] }
   7         rewriteList { arg list, inval, level;
   8                 var newlist;
   9                 if (level == 0, {
  10                         // if at bottom level, then embed all items in the stream
  11                         if (list.isSequenceableCollection, {
  12                                 // isKindOf is necessary because Integer.do would do the wrong thing..
  13                                 list.do({ arg item;
  14                                         inval = item.embedInStream(inval);
  15                                 });
  16                         },{
  17                                 inval = list.embedInStream(inval);
  18                         });
  19                 },{
  20                         if (list.isSequenceableCollection, {
  21                                 // isKindOf is necessary because Integer.do would do the wrong thing..
  22                                 list.do({ arg item;
  23                                         // lookup item in rewrite dictionary
  24                                         newlist = dict.at(item);
  25
  26                                         // found an entry ?
  27                                         if (newlist.notNil, {
  28                                                 // do another level of rewriting
  29                                                 inval = this.rewriteList( newlist, inval, level - 1 );
  30                                         },{
  31                                                 // has no dictionary entry, so embed in stream
  32                                                 inval = item.embedInStream(inval);
  33                                         });
  34                                 });
  35                         },{
  36                                 // lookup item in rewrite dictionary
  37                                 newlist = dict.at(list);
  38
  39                                 // found an entry ?
  40                                 if (newlist.notNil, {
  41                                         // do another level of rewriting
  42                                         inval = this.rewriteList( newlist, inval, level - 1 );
  43                                 },{
  44                                         // has no dictionary entry, so embed in stream
  45                                         inval = list.embedInStream(inval);
  46                                 });
  47                         });
  48                 });
  49                 ^inval;
  50         }
  51         embedInStream {  arg inval;
  52                 var outval;
  53                 var stream;
  54
  55                 stream = pattern.asStream;
  56                 while({
  57                         outval = stream.next(inval);
  58                         outval.notNil;
  59                 },{
  60                         inval = this.rewriteList(outval, inval, levels);
  61                 });
  62                 ^inval
  63         }
  64 }