The 'purposive approach' is mandated by both Federal and State Legislation - for example- the Acts Interpretation Act 1984(WA) and the Acts Interpretation Act 1901 (Cth)

What do the above mentioned statutes say about both the "purposive approach' to legislative interpretation and circumstances in which the courts may make use of "extrinsic materials' in applying the approach?

Locate and summarise the relevant sections dealing with the above matters in both the Acts Interpretation Act 1901 (Cth) and the Interpretation Act 1984 (WA).