/**
* Executes this check
*
* @param xp.compiler.ast.Node node
* @param xp.compiler.types.Scope scope
* @return bool
*/
public function verify(\xp\compiler\ast\Node $node, \xp\compiler\types\Scope $scope)
{
$access = \cast($node, 'xp.compiler.ast.ArrayAccessNode');
$type = $scope->typeOf($access->target);
$result = TypeName::$VAR;
$message = null;
if ($type->isArray()) {
$result = $type->arrayComponentType();
} else {
if ($type->isMap()) {
$result = $type->mapComponentType();
} else {
if ($type->isClass()) {
$ptr = new TypeInstance($scope->resolveType($type));
if ($ptr->hasIndexer()) {
$result = $ptr->getIndexer()->type;
} else {
$message = ['T305', 'Type ' . $ptr->name() . ' does not support offset access'];
}
} else {
if ($type->isVariable()) {
$message = ['T203', 'Array access (var)' . $access->hashCode() . ' verification deferred until runtime'];
} else {
if ('string' === $type->name) {
$result = $type;
} else {
$message = ['T305', 'Using array-access on unsupported type ' . $type->toString()];
}
}
}
}
}
$scope->setType($access, $result);
return $message;
}
/**
* Emit member access
*
* @param xp.compiler.emit.Buffer b
* @param xp.compiler.ast.MemberAccessNode access
*/
public function emitMemberAccess($b, $access)
{
$mark = $b->mark();
$this->emitOne($b, $access->target);
$type = $this->scope[0]->typeOf($access->target);
// Overload [...].length
if ($type->isArray() && 'length' === $access->name) {
$b->insert('sizeof(', $mark);
$b->append(')');
$this->scope[0]->setType($access, new TypeName('int'));
return;
}
// Manually verify as we can then rely on call target type being available
if (!$this->checks->verify($access, $this->scope[0], $this, true)) {
return;
}
// Navigation operator
if ($access->nav) {
$var = $this->tempVar();
$b->insert('(NULL === (' . $var . '=', $mark);
$b->append(') ? NULL : ')->append($var)->append('->');
$b->append($access->name);
$b->append(')');
} else {
// Rewrite for unsupported syntax
// - new Person().name to (new Person()).name
// - (<expr>).name to an inline ternary
if ($access->target instanceof InstanceCreationNode) {
$b->insert('(', $mark);
$b->append(')');
} else {
if (!$access->target instanceof ArrayAccessNode && !$access->target instanceof MethodCallNode && !$access->target instanceof MemberAccessNode && !$access->target instanceof VariableNode && !$access->target instanceof StaticMemberAccessNode && !$access->target instanceof StaticMethodCallNode) {
$var = $this->tempVar();
$b->insert('(NULL === (' . $var . '=', $mark);
$b->append(')) ? NULL : ' . $var);
}
}
$b->append('->' . $access->name);
}
// Record type
$ptr = new TypeInstance($this->resolveType($type));
if ($ptr->hasField($access->name)) {
$result = $ptr->getField($access->name)->type;
} else {
if ($ptr->hasProperty($access->name)) {
$result = $ptr->getProperty($access->name)->type;
} else {
$result = TypeName::$VAR;
}
}
$this->scope[0]->setType($access, $result);
}