blob_zero(&tags);
      blob_append(&tags, zTags, -1); 

      /* Collapse all sequences of whitespace and "," characters into
      ** a single space character */
      zBlob = blob_str(&tags);
      for(i=j=0; zBlob[i]; i++, j++){
        if( blob_isspace(zBlob[i]) || zBlob[i]==',' ){
          while( blob_isspace(zBlob[i+1]) ){ i++; }
        if( fossil_isspace(zBlob[i]) || zBlob[i]==',' ){
          while( fossil_isspace(zBlob[i+1]) ){ i++; }
          zBlob[j] = ' ';
        }else{
          zBlob[j] = zBlob[i];
        }
      }
      blob_resize(&tags, j);