[From string (line 18) ]                                                               
                                                                                       
@startuml                                                                              
!unquoted function $dump ($id)                                                         
!$data={"participants" :[                                                              
{"id": "cm" ,"label": "customer master","desc": "manages customers"},                  
{"id": "tm" ,"label": "transaction manager","desc": "manages transactions"},           
{"id": "am" ,"label": "account master","desc": "manages accounts"}                     
]}                                                                                     
                                                                                       
!foreach $part in $data.participants                                                   
  !if $part.id == $id                                                                  
    class dump {                                                                       
      - $part.id                                                                       
      + $part.label ()                                                                 
      + $part.desc ()                                                                  
      }                                                                                
  !endif                                                                               
!endfor                                                                                
!endfunction                                                                           
^^^^^                                                                                  
 This function does not have any !return directive. Declare it as a procedure instead ?