function quasiquote($ast)
{
if (!is_pair($ast)) {
return _list(_symbol("quote"), $ast);
} elseif (_symbol_Q($ast[0]) && $ast[0]->value === 'unquote') {
return $ast[1];
} elseif (is_pair($ast[0]) && _symbol_Q($ast[0][0]) && $ast[0][0]->value === 'splice-unquote') {
return _list(_symbol("concat"), $ast[0][1], quasiquote($ast->slice(1)));
} else {
return _list(_symbol("cons"), quasiquote($ast[0]), quasiquote($ast->slice(1)));
}
}
$repl_env = new Env(NULL);
function rep($str)
{
global $repl_env;
return MAL_PRINT(MAL_EVAL(READ($str), $repl_env));
}
$repl_env->set(_symbol('+'), function ($a, $b) {
return intval($a + $b, 10);
});
$repl_env->set(_symbol('-'), function ($a, $b) {
return intval($a - $b, 10);
});
$repl_env->set(_symbol('*'), function ($a, $b) {
return intval($a * $b, 10);
});
$repl_env->set(_symbol('/'), function ($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 $e) {
}
// print
function MAL_PRINT($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;
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));
}
$repl_env->set(_symbol('eval'), _function(function ($ast) {
global $repl_env;
return MAL_EVAL($ast, $repl_env);
}));
$_argv = _list();
for ($i = 2; $i < count($argv); $i++) {
$_argv->append($argv[$i]);
}
$repl_env->set(_symbol('*ARGV*'), $_argv);
// core.mal: defined using the language itself
rep("(def! not (fn* (a) (if a false true)))");
rep("(def! load-file (fn* (f) (eval (read-string (str \"(do \" (slurp f) \")\")))))");
if (count($argv) > 1) {
rep('(load-file "' . $argv[1] . '")');
exit(0);
}
// repl loop
do {
try {
$line = mal_readline("user> ");
if ($line === NULL) {
break;
}
if ($line !== "") {
function read_form($reader)
{
$token = $reader->peek();
switch ($token) {
case '\'':
$reader->next();
return _list(_symbol('quote'), read_form($reader));
case '`':
$reader->next();
return _list(_symbol('quasiquote'), read_form($reader));
case '~':
$reader->next();
return _list(_symbol('unquote'), read_form($reader));
case '~@':
$reader->next();
return _list(_symbol('splice-unquote'), read_form($reader));
case '^':
$reader->next();
$meta = read_form($reader);
return _list(_symbol('with-meta'), read_form($reader), $meta);
case '@':
$reader->next();
return _list(_symbol('deref'), read_form($reader));
case ')':
throw new Exception("unexpected ')'");
case '(':
return read_list($reader);
case ']':
throw new Exception("unexpected ']'");
case '[':
return read_list($reader, '_vector', '[', ']');
case '}':
throw new Exception("unexpected '}'");
case '{':
return read_hash_map($reader);
default:
return read_atom($reader);
}
}
