(CBN) (Normal order reduction, leftmost, outermost reduction). An argument passing convention (first provided by ALGOL 60?) where argument expressions are passed unevaLUated. This is usually implemented by passing a pointer to some code which will return the vaLUe of the argument and an environment giving the vaLUes of its free variables. This {evaLUation strategy} is guaranteed to reach a {normal form} if one exists. When used to implement functional programming languages, call-by-name is usually combined with graph reduction to avoid repeated evaLUation of the same expression. This is then known as call-by-need. The opposite of call-by-name is call-by-vaLUe where arguments are evaLUated before they are passed to a function. This is more efficient but is less likely to terminate in the presence of infinite data structures and recursive functions. Arguments to macros are usually passed using call-by-name. (1994-11-29)