1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
|
import sys, traceback
import mal_readline
from mal_types import (pr_str, sequential_Q, symbol_Q, coll_Q, list_Q,
vector_Q, hash_map_Q, new_symbol, new_function,
new_list, new_vector, new_hash_map, Env, types_ns)
from reader import (read_str, Blank)
# read
def READ(str):
return read_str(str)
# eval
def eval_ast(ast, env):
if symbol_Q(ast):
return env.get(ast)
elif list_Q(ast):
return new_list(*map(lambda a: EVAL(a, env), ast))
elif vector_Q(ast):
return new_vector(*map(lambda a: EVAL(a, env), ast))
elif hash_map_Q(ast):
keyvals = []
for k in ast.keys():
keyvals.append(EVAL(k, env))
keyvals.append(EVAL(ast[k], env))
return new_hash_map(*keyvals)
else:
return ast # primitive value, return unchanged
def EVAL(ast, env):
#print("EVAL %s" % ast)
if not list_Q(ast):
return eval_ast(ast, env)
# apply list
if len(ast) == 0: return ast
a0 = ast[0]
if "def!" == a0:
a1, a2 = ast[1], ast[2]
res = EVAL(a2, env)
return env.set(a1, res)
elif "let*" == a0:
a1, a2 = ast[1], ast[2]
let_env = Env(env)
for i in range(0, len(a1), 2):
let_env.set(a1[i], EVAL(a1[i+1], let_env))
return EVAL(a2, let_env)
else:
el = eval_ast(ast, env)
f = el[0]
return f(*el[1:])
# print
def PRINT(exp):
return pr_str(exp)
# repl
repl_env = Env()
def REP(str):
return PRINT(EVAL(READ(str), repl_env))
def _ref(k,v): repl_env.set(k, v)
_ref('+', lambda a,b: a+b)
_ref('-', lambda a,b: a-b)
_ref('*', lambda a,b: a*b)
_ref('/', lambda a,b: a/b)
while True:
try:
line = mal_readline.readline("user> ")
if line == None: break
if line == "": continue
print(REP(line))
except Blank: continue
except Exception as e:
print "".join(traceback.format_exception(*sys.exc_info()))
|
