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<?php
require_once 'readline.php';
require_once 'types.php';
require_once 'reader.php';
require_once 'printer.php';
// read
function READ($str) {
return read_str($str);
}
// eval
function eval_ast($ast, $env) {
if (_symbol_Q($ast)) {
return $env[$ast->value];
} elseif (_sequential_Q($ast)) {
if (_list_Q($ast)) {
$el = _list();
} else {
$el = _vector();
}
foreach ($ast as $a) { $el[] = MAL_EVAL($a, $env); }
return $el;
} elseif (_hash_map_Q($ast)) {
$new_hm = _hash_map();
foreach (array_keys($ast->getArrayCopy()) as $key) {
$new_hm[$key] = MAL_EVAL($ast[$key], $env);
}
return $new_hm;
} else {
return $ast;
}
}
function MAL_EVAL($ast, $env) {
if (!_list_Q($ast)) {
return eval_ast($ast, $env);
}
// apply list
$el = eval_ast($ast, $env);
$f = $el[0];
return call_user_func_array($f, array_slice($el->getArrayCopy(), 1));
}
// print
function MAL_PRINT($exp) {
return _pr_str($exp, True);
}
// repl
$repl_env = array();
function rep($str) {
global $repl_env;
return MAL_PRINT(MAL_EVAL(READ($str), $repl_env));
}
$repl_env['+'] = function ($a, $b) { return intval($a + $b,10); };
$repl_env['-'] = function ($a, $b) { return intval($a - $b,10); };
$repl_env['*'] = function ($a, $b) { return intval($a * $b,10); };
$repl_env['/'] = function ($a, $b) { return intval($a / $b,10); };
// repl loop
do {
try {
$line = mal_readline("user> ");
if ($line === NULL) { break; }
if ($line !== "") {
print(rep($line) . "\n");
}
} catch (BlankException $e) {
continue;
} catch (Exception $e) {
echo "Error: " . $e->getMessage() . "\n";
echo $e->getTraceAsString() . "\n";
}
} while (true);
?>
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