extern bl_string_replace(text:String, pat:BP, replacement:String):String
extern bl_string_repeat(str:String, n:Int):String
deftype Cord:Pointer
empty_cord := (0):Cord
deftype StringPointer:Pointer
extern CORD_cat(cord:Cord, str:String):Cord
extern CORD_to_const_char_star(cord:Cord):StringPointer
extern CORD_from_file_eager(fp:Pointer):Cord

def tostring(cord:Cord):String
    return "$(CORD_to_const_char_star(cord):String)"

def join_strings(strs:[String], glue:String?):String
    buf := empty_cord
    for str in strs
        buf = CORD_cat(buf, str)
    between
        buf = CORD_cat(buf, glue) if glue
    return "$(CORD_to_const_char_star(buf):String)"

macro join(strs, glue)
    join_strings(["$x" for x in strs], glue)

macro join(strs)
    join_strings(["$x" for x in strs])

nums := [6,7,8]

$puts "$(nums | join)"
$puts "$(nums | join ",")"