higher-order macro
A means of expressing certain {higher-order functions} in a
first order language. Proposed by Phil Wadler. Higher-order
macros cannot be recursive at the top level but they may
contain recursive definitions. E.g.
map f l = m l
where
m [] = []
m (x:xs) = f x : m xs
Expanding a call to this macro is equivalent to specialising a
call to map in its first argument.
See {partial evaluation}.