mirror of
https://github.com/kanaka/mal.git
synced 2024-11-10 12:47:45 +03:00
70 lines
1.8 KiB
Io
70 lines
1.8 KiB
Io
MalTypes
|
|
MalReader
|
|
|
|
READ := method(str, MalReader read_str(str))
|
|
|
|
eval_ast := method(ast, env,
|
|
(ast type) switch(
|
|
"MalSymbol", env get(ast),
|
|
"MalList", MalList with(ast map(a, EVAL(a, env))),
|
|
"MalVector", MalVector with(ast map(a, EVAL(a, env))),
|
|
"MalMap",
|
|
m := MalMap clone
|
|
ast foreach(k, v,
|
|
keyObj := MalMap keyToObj(k)
|
|
m atPut(MalMap objToKey(EVAL(keyObj, env)), EVAL(v, env))
|
|
)
|
|
m,
|
|
ast
|
|
)
|
|
)
|
|
|
|
EVAL := method(ast, env,
|
|
if(ast type != "MalList", return(eval_ast(ast, env)))
|
|
if(ast isEmpty, return ast)
|
|
if(ast at(0) type == "MalSymbol",
|
|
ast at(0) val switch(
|
|
"def!",
|
|
return(env set(ast at(1), EVAL(ast at(2), env))),
|
|
"let*",
|
|
letEnv := Env with(env)
|
|
varName := nil
|
|
ast at(1) foreach(i, e,
|
|
if(i % 2 == 0,
|
|
varName := e,
|
|
letEnv set(varName, EVAL(e, letEnv))
|
|
)
|
|
)
|
|
return(EVAL(ast at(2), letEnv))
|
|
)
|
|
)
|
|
|
|
// Apply
|
|
el := eval_ast(ast, env)
|
|
f := el at(0)
|
|
args := el rest
|
|
f callWithArgList(args)
|
|
)
|
|
|
|
PRINT := method(exp, exp malPrint(true))
|
|
|
|
repl_env := Env with(nil)
|
|
repl_env set(MalSymbol with("+"), block(a, b, a + b))
|
|
repl_env set(MalSymbol with("-"), block(a, b, a - b))
|
|
repl_env set(MalSymbol with("*"), block(a, b, a * b))
|
|
repl_env set(MalSymbol with("/"), block(a, b, a / b))
|
|
|
|
RE := method(str, EVAL(READ(str), repl_env))
|
|
|
|
REP := method(str, PRINT(RE(str)))
|
|
|
|
loop(
|
|
line := MalReadline readLine("user> ")
|
|
if(line isNil, break)
|
|
if(line isEmpty, continue)
|
|
e := try(REP(line) println)
|
|
e catch(Exception,
|
|
("Error: " .. (e error)) println
|
|
)
|
|
)
|