def repl():
# set up base environment
env = Env(outer=None)
for k, v in ns.items():
env.set(k, v)
env.set(SYMBOL_EVAL, lambda ast: EVAL(ast, env=env)) # `eval` added to ns
s = """
(def! load-file
(fn* (f)
(eval (read-string (str "(do " (slurp f) ")")))))
"""
EVAL(READ(s), env=env)
# read-eval-print loop
while True:
try:
s = input("=> ")
rep(s, env)
except Exception as e:
print("error: {0}".format(e))
def PRINT(print_in):
return printer.pr_str(print_in)
def rep(rep_in):
read_out = READ(rep_in)
eval_out = EVAL(read_out, repl_env)
print_out = PRINT(eval_out)
return print_out
repl_env = Env()
# Add namespace variables to repl environment
for key, value in ns.items():
repl_env.set(key, value)
# Add the eval operator
repl_env.set('eval', lambda ast: EVAL(ast, repl_env))
rep("(def! not (fn* (a) (if a false true)))")
rep('(def! load-file (fn* (f) (eval (read-string (str \"(do \" (slurp f) \")\")))))'
)
while True:
try:
usr_input = input("user> ")
rep_result = rep(usr_input)
if rep_result is not None:
print(rep_result)
import reader
import printer
import mal_types
from env import Env
from core import ns
repl_env = Env()
repl_env.set('eval', lambda ast: EVAL(ast, repl_env))
for k, v in ns.items():
repl_env.set(k, v)
def READ(string):
return reader.read_str(string)
def EVAL(ast, env):
while True:
if not isinstance(ast, mal_types.list_types):
return eval_ast(ast, env)
elif not ast:
return ast
elif isinstance(ast, mal_types.list_types):
if len(ast) == 0:
return ast
if isinstance(ast[0], mal_types.MalSymbol):
if ast[0].data == 'def!':
value = EVAL(ast[2], env)
env.set(ast[1].data, value)
return value
#!/usr/bin/env python3
import readline
import sys
import reader, printer
from types import *
from env import Env
from core import ns
repl_env = Env(None)
repl_env.set('eval', lambda ast: EVAL(ast, repl_env))
for name, f in ns.items():
repl_env.set(name, f)
def READ(s):
return reader.read_str(s)
def EVAL(ast, env):
while True: # allow tail call optimization (TCO)
if isinstance(ast, MalList):
if len(ast) == 0:
return ast
call = ast[0]
if call == 'def!':
f_name, f_def, *others = ast[1:]
if others:
