anchor.diff:                  </selftest>
   
   : count         ( string -- string length ) // Get length of the given string
  -                [ s" push(function(){push(tos().length)})" jsEvalNo , ] ;
  +                \ [ s" push(function(){push(tos().length)})" jsEvalNo , ] ;
  +                py: push(len(tos())) ;
   
                   <selftest>
                       *** count
  
positive.code:                 </selftest>
  
  : variable      ( <string> -- ) // Create a variable.
                  create 0 , [ char push(function(){last().type='colon-variable'}) jsEvalNo , ] ;
                  
  : +!            ( n addr -- ) // Add n into addr, addr is a variable.
                  swap over @ swap + swap ! ;
  
                  
  : ?             @ . ; // ( a -- ) print value of the variable.
  
                  <selftest>
  
negative.code: 
  : [then]        ( -- ) // Conditional compilation [if] [else] [then]
                  ; immediate
                  
  : ::    ( obj <foo.bar> ) // Simplified form of "obj py: pop().foo.bar" w/o return value
          BL word <py> tos()[0]=='[' or tos()[0]=='(' </pyV> 
          if char pop() else char pop(). then 
          swap + compiling if </py> 
          else [compile] </py> then ; immediate
          
  : :>    ( obj <foo.bar> ) // Simplified form of "obj js> pop().foo.bar" w/return value
          BL word <py> tos()[0]=='[' or tos()[0]=='(' </pyV>
          if char pop() else char pop(). then 
          swap + compiling if </pyV> 
          else [compile] </pyV> then ; immediate
  stop _stop_    
  
  : (             ( <str> -- ) // Ignore the comment down to ')', can be nested but must be balanced
                  js> nextstring(/\(|\)/).str \ word 固定會吃掉第一個 character 故不適用。
  