{"ast_node_type":"variable","tokens":[{"end":54,"kind":"keyword","start":0,"text":"let"}]}
        let src_range = alloc_range(src_offset, size);
        let src_alloc = self.get_alloc_raw(src_alloc_id)?;
        assert!(!self.memory.validation_in_progress.get(), "we can't be copying during validation");