# Exercise Session 06

*This summarizes activities done in class on 22 October 2008.*

Type checking and evaluation for simply typed lambda calculus

Solved exercises:

1) Prove that the following program is type correct:

class Max { int max (int x, int y) { int res; res = (x > y) ? x : y; return res; } }

2) Type check the following simply typed lambda terms:

a)

b)

The initial environment contains the following types:

3) Find an environment under which the term gas type .