OZ Programming Language

% Q3 Concurrency and exceptions. % Consider the following control abstraction that implements tryfinally:

proc {TryFinally S1 S2} B Y in try {S1} B=false catch X then B=true Y=X end {S2} if B then raise Y end end end

% Using the abstract machine semantics as a guide, determine the different possible results of the following program:

local U=1 V=2 in {TryFinally proc {$} thread {TryFinally proc {$} U=V end proc {$} {Browse bing} end} end end proc {$} {Browse bong} end} end

% How many different results are possible?

% How many different executions are possible?