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import rdstdin, tables, sequtils, types, reader, printer, env
proc read(str: string): MalType = str.read_str
proc eval(ast: MalType, env: var Env): MalType
proc eval_ast(ast: MalType, env: var Env): MalType =
case ast.kind
of Symbol:
result = env.get(ast.str)
of List:
result = list ast.list.mapIt(MalType, it.eval(env))
of Vector:
result = vector ast.list.mapIt(MalType, it.eval(env))
of HashMap:
result = hash_map()
for k, v in ast.hash_map.pairs:
result.hash_map[k] = v.eval(env)
else:
result = ast
proc eval(ast: MalType, env: var Env): MalType =
case ast.kind
of List:
let
a0 = ast.list[0]
a1 = ast.list[1]
a2 = ast.list[2]
case a0.str
of "def!":
result = env.set(a1.str, a2.eval(env))
of "let*":
var letEnv: Env
letEnv.deepCopy(env)
case a1.kind
of List, Vector:
for i in countup(0, a1.list.high, 2):
letEnv.set(a1.list[i].str, a1.list[i+1].eval(letEnv))
else: discard
result = a2.eval(letEnv)
else:
let el = ast.eval_ast(env)
result = el.list[0].fun(el.list[1 .. -1])
else:
result = ast.eval_ast(env)
proc print(exp: MalType): string = exp.pr_str
template wrapNumberFun(op: expr): expr =
fun proc(xs: varargs[MalType]): MalType = number op(xs[0].number, xs[1].number)
var repl_env = initEnv()
repl_env.set("+", wrapNumberFun(`+`))
repl_env.set("-", wrapNumberFun(`-`))
repl_env.set("*", wrapNumberFun(`*`))
repl_env.set("/", wrapNumberFun(`div`))
#repl_env.set("/", wrapNumberFun(proc(x,y: int): int = int(x.float / y.float)))
proc rep(str: string): string =
str.read.eval(repl_env).print
while true:
try:
let line = readLineFromStdin("user> ")
echo line.rep
except:
echo getCurrentExceptionMsg()
echo getCurrentException().getStackTrace()
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