Asterisk Len & Execif

1. exten=>001,1,Answer()
   same=>n,Noop(${CALLERID(num)})
   same=>n,Set(ARG1=${CALLERID(num)})
   same=>n,Noop( len of ${LEN(${ARG1})})
   same=>n,ExecIf($[${LEN(${ARG1})}= 11]?Set(CALLERID(num)=${ARG1:0:7}${RAND(1000,9999)}))
   same=>n,ExecIf($[${LEN(${ARG1})}> 11]?Set(CALLERID(num)=${ARG1:0:7}))