def rep(line):
try:
print(pr_str(eval(read_str(line), repl_env)))
except Exception as e:
if isinstance(e.args[0], Val):
print(pr_str(Val("error", e.args[0])))
else:
print(pr_str(Val("error", Val("string", str(e)))))
def eval(ast, env):
if ast.type != "list":
return eval_ast(ast, env)
if len(ast.value) == 0:
return ast
symbol = ast.value[0].value
if symbol == "def!":
evaluated = eval(ast.value[2], env)
env.set(ast.value[1].value, evaluated)
return evaluated
if symbol == "let*":
new_env = Env(env)
params = ast.value[1].value
i = 0
while i < len(params):
new_env.set(params[i].value, eval(params[i + 1], new_env))
i += 2
return eval(ast.value[2], new_env)
if symbol == "do":
evaluated = None
for i in ast.value[1:]:
evaluated = eval(i, env)
return evaluated
if symbol == "if":
evaluated = None
cond = eval(ast.value[1], env)
if cond.type != "nil" and (cond.type != "bool" or cond.value == True):
return eval(ast.value[2], env)
if len(ast.value) > 3:
return eval(ast.value[3], env)
return Val("nil", [])
if symbol == "fn*":
def func(*exprs_t):
new_env = Env(env)
params = ast.value[1].value
exprs = list(exprs_t)
i = 0
while i < len(params):
if params[i].value == "&":
new_env.set(params[i + 1].value, Val("list", exprs[i:]))
break
new_env.set(params[i].value, exprs[i])
i += 1
return eval(ast.value[2], new_env)
return Val("fn", func)
new_ast = eval_ast(ast, env)
fn = new_ast.value[0]
return fn.value(*new_ast.value[1:])
#!/usr/bin/python3
# -*- coding: utf-8 -*-
import sys
from reader import read_str, Val
from printer import pr_str
from env import Env
from core import ns
repl_env = Env()
for key in ns:
repl_env.set(key, ns[key])
repl_env.set("eval", Val("fn", lambda a: eval(a, repl_env)))
repl_env.set("*host-language*", Val("string", "Python"))
def eval_ast(ast, env):
if ast.type == "symbol":
return env.get(ast.value)
if ast.type in ("list", "vector"):
items = map(lambda ast: eval(ast, env), ast.value)
return Val(ast.type, items)
if ast.type == "hashmap":
new_val = {}
for key, value in ast.value.items():
new_val[key] = eval(value, env)
return Val("hashmap", new_val)
return ast
def is_pair(ast):