Function tx_node_value 

#[unsafe(no_mangle)]
pub unsafe extern "C" fn tx_node_value(
    doc: *mut TxDocument,
    node: TxNodeId,
) -> *const c_char

Returns the “value” of a node based on its type:

• Element → tag name
• Text → text content
• Comment → comment text
• Declaration → declaration name
• Unknown → raw content
• Document → empty string

Safety

doc must be a valid, non-null pointer to a TxDocument.