public Block LookupBlock (Block from)
{
Block result;
if (!block_map.TryGetValue (from, out result)) {
result = (Block) from.Clone (this);
}
return result;
}
public Block LookupBlock (Block from)
{
Block result = (Block) block_map [from];
if (result == null){
result = (Block) from.Clone (this);
block_map [from] = result;
}
return result;
}