def expand_clauses(clauses):
if clauses is EmptyList:
return Boolean(False)
first = car(clauses)
rest = cdr(clauses)
if is_cond_else_clause(first):
if rest is EmptyList:
return sequence_expr(cond_actions(first))
else:
raise ValueError('ELSE caluse isn\'t last: %s' % clauses)
else:
return make_if(cond_predicate(first),
sequence_expr(cond_actions(first)), expand_clauses(rest))
def rest_operands(ops):
return cdr(ops)
def operands(expr):
return cdr(expr)
def rest_exprs(seq):
return cdr(seq)
def is_last_expr(seq):
return cdr(seq) is EmptyList
def begin_actions(expr):
return cdr(expr)
def inner(arg, count):
if arg is EmptyList:
return count
return inner(cdr(arg), count + 1)
def cond_clauses(expr):
return cdr(expr)
def cond_actions(clause):
return cdr(clause)
def inner(expr):
if expr is EmptyList:
return EmptyList
return cons(cadar(expr), inner(cdr(expr)))
def inner(arg, count):
if arg is EmptyList:
return count
return inner(cdr(arg), count + 1)
def rest_exprs(seq):
return cdr(seq)
def is_last_expr(seq):
return cdr(seq) is EmptyList
def begin_actions(expr):
return cdr(expr)
