Cardinality, denumerability, Cauchy's first diagonal argument for denumerable union of denumberable sets, Cantor's second Diagonalization technique
Polymorphic lists and curried functions, higher-order functions
Reference Material, Notes, Books, and online resources
I do not prescribe a particular text book, but the following books and notes can be used as references.
[SAK02] S. Arun-Kumar: Introduction to Logic for Computer Science, see here.
[E01] H. B. Enderton.: Mathematical Introduction to Logic, Academic Press, Elsevier, 2001 (Rs 295.00)
[B93] M. Ben-Ari: Mathematical Logic for Computer Science, Prentice
[EFT94] H.-D. Ebbinghaus, J. Flum, W. Thomas: Mathematical Logic, Springer Verlag 1994.
[K97] John Kelly: The Essence of Logic, Prentice-Hall of India, 1997 (Rs 95.00).
The Functional Approach to Programming, G. Cousineau and M. Mauny, Cambridge University Press, 1998. Warning: Not easily available and somewhat expensive. Code is in OCaml, which is luckily not too different from SML.
ML for the Working Programmer, Larry Paulson, Cambridge University Press. Warning: Not easily available and somewhat expensive.
Structure and Interpretation of Computer Programs, H Abelson and G Sussmann, MIT Press.