Is there any way to clone or modify ast?

[LIMPIX31]

I want to get owned Program to be able modify it. But the Program has Boxes that not owns the data, only stores &'alloc mut T

[Boshen]

The transformer mutates the AST, for example

oxc/crates/oxc_transformer/src/es2022/class_static_block.rs

Lines 77 to 101 in 86ee074

	let params = self.ast.formal_parameters(
	SPAN,
	FormalParameterKind::ArrowFormalParameters,
	self.ast.new_vec(),
	None,
	);
	let statements = self.ast.move_statement_vec(&mut block.body);
	let function_body =
	self.ast.function_body(SPAN, self.ast.new_vec(), statements);
	let callee = self.ast.arrow_function_expression(
	SPAN,
	false,
	false,
	params,
	function_body,
	None,
	None,
	);
	let callee = self.ast.parenthesized_expression(SPAN, callee);
	let value =
	self.ast.call_expression(SPAN, callee, self.ast.new_vec(), false, None);

Mutating a lifetimed struct with allocators in Rust is kind of painful, so ideally you want to use a builder pattern for the AST nodes https://github.com/oxc-project/oxc/blob/main/crates/oxc_ast/src/ast_builder.rs