def apply_primitive(name, vals):
"""Applies the primitive function `name`, with args=`vals`."""
if is_eq(name, quote("cons")):
return cons(first(vals), second(vals))
if is_eq(name, quote("car")):
return car(first(vals))
if is_eq(name, quote("cdr")):
return cdr(first(vals))
if is_eq(name, quote("null?")):
return is_null(first(vals))
if is_eq(name, quote("eq?")):
return is_eq(first(vals), second(vals))
if is_eq(name, quote("atom?")):
return _is_atom(first(vals))
if is_eq(name, quote("zero?")):
return is_zero(first(vals))
if is_eq(name, quote("add1")):
return add1(first(vals))
if is_eq(name, quote("sub1")):
return sub1(first(vals))
if is_eq(name, quote("number?")):
return is_number(first(vals))
def render_pair(asker, x):
return asker.reply(answer=strings.concat(
strings.concat(
T.from_str("("),
asker.ask_firmly(render(fields.get(pairs.first(), x))),
),
strings.concat(
T.from_str(", "),
strings.concat(
asker.ask_firmly(render(fields.get(pairs.first(), x))),
T.from_str(")")
)
)
))
def itemize_cons(asker, head, tail):
a = fields.get(asker, pairs.first(), head)
b = fields.get(asker, pairs.second(), head)
return asker.reply(answer=cons(a, b, from_items(tail)))
def is_non_primitive(l):
"""Asks the question if `l` is a primitive."""
return is_eq(first(l), quote("non-primitive"))