function id2s takes integer id returns string
local integer i=1
local string array s
local integer array idx
set idx[1]=id/256/256/256
set idx[2]=ModuloInteger(id/256/256,256)
set idx[3]=ModuloInteger(id/256,256)
set idx[4]=ModuloInteger(id,256)
loop
exitwhen i>4
if idx[i]>=65 and idx[i]<=90 then
set s[i]=SubString("ABCDEFGHIJKLMNOPQRSTUVWXYZ",idx[i]-65,idx[i]-64)
elseif idx[i]>=97 and idx[i]<=122 then
set s[i]=SubString("abcdefghijklmnopqrstuvwxyz",idx[i]-97,idx[i]-96)
elseif idx[i]>=48 and idx[i]<=57 then
set s[i]=SubString("0123456789",idx[i]-48,idx[i]-47)
endif
set i=i+1
endloop
return s[1]+s[2]+s[3]+s[4]
endfunction