private function evalCode($code, array $envVars = array())
{
$parser = new Scheme_Parser($code);
$expr = $parser->parse($code);
$env = $this->rootEnv->createChildEnv();
$env->bindAll($envVars);
return $this->interp->evaluate($env, $expr);
}
public function letrec(array $args, Scheme_Env $env)
{
$this->requireExactly(2, $args);
$bindings = $args[0];
$body = $args[1];
$interpreter = $env->getInterpreter();
$newEnv = $env->createChildEnv();
$this->requireList($bindings);
$initedBindings = array();
foreach ($bindings->listToArray() as $binding) {
$this->requireList($binding);
$bindingArray = $binding->listToArray();
$this->requireExactly(2, $bindingArray);
$var = $bindingArray[0];
$expr = $bindingArray[1];
$this->requireSymbol($var);
$value = $interpreter->evaluate($newEnv, $expr);
$initedBindings[$var->value] = $value;
}
$newEnv->bindAll($initedBindings);
return new Scheme_TailCall($body, $newEnv);
}