function MAL_EVAL($ast, $env)
{
while (true) {
#echo "MAL_EVAL: " . _pr_str($ast) . "\n";
if (!_list_Q($ast)) {
return eval_ast($ast, $env);
}
// apply list
$ast = macroexpand($ast, $env);
if (!_list_Q($ast)) {
return eval_ast($ast, $env);
}
if ($ast->count() === 0) {
return $ast;
}
$a0 = $ast[0];
$a0v = _symbol_Q($a0) ? $a0->value : $a0;
switch ($a0v) {
case "def!":
$res = MAL_EVAL($ast[2], $env);
return $env->set($ast[1], $res);
case "let*":
$a1 = $ast[1];
$let_env = new Env($env);
for ($i = 0; $i < count($a1); $i += 2) {
$let_env->set($a1[$i], MAL_EVAL($a1[$i + 1], $let_env));
}
$ast = $ast[2];
$env = $let_env;
break;
// Continue loop (TCO)
// Continue loop (TCO)
case "quote":
return $ast[1];
case "quasiquote":
$ast = quasiquote($ast[1]);
break;
// Continue loop (TCO)
// Continue loop (TCO)
case "defmacro!":
$func = MAL_EVAL($ast[2], $env);
$func->ismacro = true;
return $env->set($ast[1], $func);
case "macroexpand":
return macroexpand($ast[1], $env);
case "php*":
$res = eval($ast[1]);
switch (gettype($res)) {
case "array":
if ($res !== array_values($res)) {
$new_res = _hash_map();
$new_res->exchangeArray($res);
return $new_res;
} else {
return call_user_func_array('_list', $res);
}
default:
return $res;
}
case "try*":
$a1 = $ast[1];
$a2 = $ast[2];
if ($a2[0]->value === "catch*") {
try {
return MAL_EVAL($a1, $env);
} catch (Error $e) {
$catch_env = new Env($env, array($a2[1]), array($e->obj));
return MAL_EVAL($a2[2], $catch_env);
} catch (Exception $e) {
$catch_env = new Env($env, array($a2[1]), array($e->getMessage()));
return MAL_EVAL($a2[2], $catch_env);
}
} else {
return MAL_EVAL($a1, $env);
}
case "do":
eval_ast($ast->slice(1, -1), $env);
$ast = $ast[count($ast) - 1];
break;
// Continue loop (TCO)
// Continue loop (TCO)
case "if":
$cond = MAL_EVAL($ast[1], $env);
if ($cond === NULL || $cond === false) {
if (count($ast) === 4) {
$ast = $ast[3];
} else {
$ast = NULL;
}
} else {
$ast = $ast[2];
}
break;
// Continue loop (TCO)
// Continue loop (TCO)
case "fn*":
return _function('MAL_EVAL', 'native', $ast[2], $env, $ast[1]);
default:
$el = eval_ast($ast, $env);
$f = $el[0];
$args = array_slice($el->getArrayCopy(), 1);
if ($f->type === 'native') {
$ast = $f->ast;
$env = $f->gen_env($args);
// Continue loop (TCO)
} else {
return $f->apply($args);
}
}
}
}
function MAL_EVAL($ast, $env)
{
while (true) {
#echo "MAL_EVAL: " . _pr_str($ast) . "\n";
if (!_list_Q($ast)) {
return eval_ast($ast, $env);
}
// apply list
$ast = macroexpand($ast, $env);
if (!_list_Q($ast)) {
return eval_ast($ast, $env);
}
if ($ast->count() === 0) {
return $ast;
}
$a0 = $ast[0];
$a0v = _symbol_Q($a0) ? $a0->value : $a0;
switch ($a0v) {
case "def!":
$res = MAL_EVAL($ast[2], $env);
return $env->set($ast[1], $res);
case "let*":
$a1 = $ast[1];
$let_env = new Env($env);
for ($i = 0; $i < count($a1); $i += 2) {
$let_env->set($a1[$i], MAL_EVAL($a1[$i + 1], $let_env));
}
$ast = $ast[2];
$env = $let_env;
break;
// Continue loop (TCO)
// Continue loop (TCO)
case "quote":
return $ast[1];
case "quasiquote":
$ast = quasiquote($ast[1]);
break;
// Continue loop (TCO)
// Continue loop (TCO)
case "defmacro!":
$func = MAL_EVAL($ast[2], $env);
$func->ismacro = true;
return $env->set($ast[1], $func);
case "macroexpand":
return macroexpand($ast[1], $env);
case "do":
eval_ast($ast->slice(1, -1), $env);
$ast = $ast[count($ast) - 1];
break;
// Continue loop (TCO)
// Continue loop (TCO)
case "if":
$cond = MAL_EVAL($ast[1], $env);
if ($cond === NULL || $cond === false) {
if (count($ast) === 4) {
$ast = $ast[3];
} else {
$ast = NULL;
}
} else {
$ast = $ast[2];
}
break;
// Continue loop (TCO)
// Continue loop (TCO)
case "fn*":
return _function('MAL_EVAL', 'native', $ast[2], $env, $ast[1]);
default:
$el = eval_ast($ast, $env);
$f = $el[0];
$args = array_slice($el->getArrayCopy(), 1);
if ($f->type === 'native') {
$ast = $f->ast;
$env = $f->gen_env($args);
// Continue loop (TCO)
} else {
return $f->apply($args);
}
}
}
}
}
// print
function MAL_PRINT($exp)
{
return _pr_str($exp, True);
}
// repl
$repl_env = new Env(NULL);
function rep($str)
{
global $repl_env;
return MAL_PRINT(MAL_EVAL(READ($str), $repl_env));
}
// core.php: defined using PHP
foreach ($core_ns as $k => $v) {
$repl_env->set(_symbol($k), _function($v));
}
// core.mal: defined using the language itself
rep("(def! not (fn* (a) (if a false true)))");
// repl loop
do {
try {
$line = mal_readline("user> ");
if ($line === NULL) {
break;
}
if ($line !== "") {
print rep($line) . "\n";
}
} catch (BlankException $e) {
continue;
