def lib_append(*args):
"""(append '(1 2) '(a b))
or
(append '(1 2) 'x)
"""
if len(args) == 0:
return NIL
import copy
lsts = [copy.deepcopy(x) for x in args]
res = lsts[-1]
for lst in reversed(lsts[:-1]):
try:
if lst.isnil:
continue
p = lst
while not cdr(p).isnil:
p = cdr(p)
p[1] = res
res = lst
except SchemeError:
raise SchemeError('expects proper list, given %s' % (to_str(p)))
if not isinstance(res, Pair):
return res
if lib_islist(lsts[-1]):
res.islist = True
else:
res.islist = False
if res.islist:
res.length = sum([x.length for x in args])
else:
res.length = 0
return res
def testDeepParsing(self):
"""S-expressions that require deep recursion.
"""
import sys
sys.setrecursionlimit(50)
cases = [("'"*1000 + "x", "(quote "*1000 + "x" + ")"*1000), \
("(x . "*1000 + "()" + ")"*1000, "(" + "x " * 999 + "x)")]
for case in cases:
sexp = self.parser.parse(self.tokenizer.tokenize(case[0] + '\n'))[0]
self.assertEqual(to_str(sexp), case[1])
def lib_list_tail(p, start):
"""(list-tail '(a b c) 1)
"""
orig = p
try:
now = 0
while now != start:
p = cdr(p)
now += 1
return p
except SchemeError:
raise SchemeError('index %s is too large for %s' % (start, to_str(orig)))
def testStringRepr(self):
"""Test the string representation of the parsed S-expressions.
"""
cases = [("'x", "(quote x)"), \
("''x", "(quote (quote x))"), \
("'(quote 'x)", "(quote (quote (quote x)))"), \
("'(quote 'x 'y)", "(quote (quote (quote x) (quote y)))"), \
("(a b c)", "(a b c)"), \
("'(a b c)", "(quote (a b c))"), \
("(a b . c)", "(a b . c)"), \
("(a . (b . (c . ())))", "(a b c)"), \
("(a . (b . (c . d)))", "(a b c . d)")]
for case in cases:
sexp = self.parser.parse(self.tokenizer.tokenize(case[0] + '\n'))[0]
self.assertEqual(to_str(sexp), case[1])
def g(p):
try:
return func(p)
except Exception:
raise SchemeError('expect %sable pairs, given %s' % (cxr, to_str(p)))
def lib_length(p):
"""(length '(1 2 3))
"""
if not p.islist:
raise SchemeError('expects proper list, given %s' % (to_str(p)))
return p.length