how to properly init a Table of seq

[chancyk]

@ElegantBeef

Is there a way to overload `[]` to provide a default if the key doesn't exist? 
Something like:
    
    
    proc `[]`(table: var Table[string, seq[int]], key: string): var seq[int] =
        if table.hasKey(key):
            result = table[key]
        else:
            result = newSeq[int]()
    
    
    Run

This fails with `expression has no address`.