def scheme_read(src):
"""Read the next expression from SRC, a Buffer of tokens.
>>> lines = ["(+ 1 ", "(+ 23 4)) ("]
>>> src = Buffer(tokenize_lines(lines))
>>> print(scheme_read(src))
(+ 1 (+ 23 4))
>>> read_line("'hello")
Pair('quote', Pair('hello', nil))
>>> print(read_line("(car '(1 2))"))
(car (quote (1 2)))
"""
if src.current() is None:
raise EOFError
val = src.pop()
if val == "nil":
return nil
elif type(val) is int or type(val) is float:
return scnum(val)
elif type(val) is bool:
return scbool(val)
elif val not in DELIMITERS:
if val[0] == '"':
return scstr(eval(val))
else:
return intern(val)
elif val == "'":
return Pair(intern('quote'), Pair(scheme_read(src), nil))
elif val == "(":
return read_tail(src)
else:
raise SyntaxError("unexpected token: {0}".format(val))
def scheme_read(src):
"""Read the next expression from SRC, a Buffer of tokens.
>>> lines = ["(+ 1 ", "(+ 23 4)) ("]
>>> src = Buffer(tokenize_lines(lines))
>>> print(scheme_read(src))
(+ 1 (+ 23 4))
>>> read_line("'hello")
Pair('quote', Pair('hello', nil))
>>> print(read_line("(car '(1 2))"))
(car (quote (1 2)))
"""
if src.current() is None:
raise EOFError
val = src.pop()
if type(val) is int or type(val) is float:
return scnum(val)
elif type(val) is bool:
return scbool(val)
elif val not in DELIMITERS:
if val[0] == '"':
return scstr(eval(val))
else:
return intern(val)
elif val == "'":
"*** YOUR CODE HERE ***"
return Pair('quote', Pair(scheme_read(src), nil))
elif val == "(":
return read_tail(src)
else:
raise SyntaxError("unexpected token: {0}".format(val))
def scheme_read(src):
# import pdb; pdb.set_trace()
"""Read the next expression from SRC, a Buffer of tokens.
>>> lines = ["(+ 1 ", "(+ 23 4)) ("]
>>> src = Buffer(tokenize_lines(lines))
>>> print(scheme_read(src))
(+ 1 (+ 23 4))
>>> read_line("(+ 1 2)")
Pair('+', Pair(1, Pair(2, nil)))
>>> read_line("'hello")
Pair('quote', Pair('hello', nil))
>>> print(read_line("(car '(1 2))"))
(car (quote (1 2)))
"""
if src.current() is None:
raise EOFError
val = src.pop()
if val == "nil":
return nil
elif type(val) is int or type(val) is float:
return scnum(val)
elif type(val) is bool:
return scbool(val)
# self-evaluating
elif val not in DELIMITERS:
if val[0] == '"':
return scstr(eval(val))
else:
return intern(val)
elif val == "'":
"*** YOUR CODE HERE ***"
# nested Pair eventually matches the required structure
rest = scheme_read(src)
return Pair("quote", Pair(rest, nil))
elif val == "(":
return read_tail(src)
else:
raise SyntaxError("unexpected token: {0}".format(val))
def scheme_read(src):
# import pdb; pdb.set_trace()
"""Read the next expression from SRC, a Buffer of tokens.
>>> lines = ["(+ 1 ", "(+ 23 4)) ("]
>>> src = Buffer(tokenize_lines(lines))
>>> print(scheme_read(src))
(+ 1 (+ 23 4))
>>> read_line("(+ 1 2)")
Pair('+', Pair(1, Pair(2, nil)))
>>> read_line("'hello")
Pair('quote', Pair('hello', nil))
>>> print(read_line("(car '(1 2))"))
(car (quote (1 2)))
"""
if src.current() is None:
raise EOFError
val = src.pop()
if val == "nil":
return nil
elif type(val) is int or type(val) is float:
return scnum(val)
elif type(val) is bool:
return scbool(val)
# self-evaluating
elif val not in DELIMITERS:
if val[0] == '"':
return scstr(eval(val))
else:
return intern(val)
elif val == "'":
"*** YOUR CODE HERE ***"
# nested Pair eventually matches the required structure
rest = scheme_read(src)
return Pair("quote", Pair(rest, nil))
elif val == "(":
return read_tail(src)
else:
raise SyntaxError("unexpected token: {0}".format(val))