Hi, I'm looking to do a comparison between 2 simple functions to see if they are equivalent but I appear to be running into some problems if anyone can help. The two functions I want to compare are f (g a) and g (f a). I have f defined and g defined as f :: a -> a f = undefined g :: a -> a. g = undefined The compiler was complaining about the type signature lacking a binding so added undefined to get around the error. I understand that I must be missing something very basic as they look incomparable in this form. Any suggestions of what changes I should make such a comparison practical? Many thanks, Stephen -- This email originated from DIT. If you received this email in error, please delete it from your system. Please note that if you are not the named addressee, disclosing, copying, distributing or taking any action based on the contents of this email or attachments is prohibited. www.dit.ie Is ó ITBÁC a tháinig an ríomhphost seo. Má fuair tú an ríomhphost seo trí earráid, scrios de do chóras é le do thoil. Tabhair ar aird, mura tú an seolaí ainmnithe, go bhfuil dianchosc ar aon nochtadh, aon chóipeáil, aon dáileadh nó ar aon ghníomh a dhéanfar bunaithe ar an ábhar atá sa ríomhphost nó sna hiatáin seo. www.dit.ie Tá ITBÁC ag aistriú go Gráinseach Ghormáin – DIT is on the move to Grangegorman http://www.dit.ie/grangegorman