********** source program **********
fn f (0 = Int: x) -> Int {
return 0;

}
fn main () -> Int {
var Int: a = 0;
var Int: b = 1;
f(0 = a);
b = a;
return b;

}
********** type checking **********
--- step exp Int --->
--- step exp Int --->
--- step exp Int --->
--- step exp Int --->
--- step exp Int --->
--- step exp Int --->
--- step exp Int --->
--- step exp Int --->

********** type checking complete **********
fn f (0 = Int: x) -> Int {
return 0;
}
fn main () -> Int {
var Int: a = 0;
var Int: b = 1;
f(0 = a);
b = a;
return b;
}
********** starting execution **********
********** initializing globals **********
--- step exp (0 = Int: x) --->
--- step exp Int: x --->
--- step exp Int --->
--- handle value Int with Int: x<1>(Int,) --->
--- handle value Int: x with (0 = Int: x)<1>(Int: x,) --->
--- step exp () --->
********** calling main function **********
{
stack: top{main()<-1>}
heap: Int: x, fun<f>, fun<main>, 
env: main: fun<main>, f: fun<f>, 
}
--- step exp main() --->
{
stack: top{main<-1> :: main()<0>}
heap: Int: x, fun<f>, fun<main>, 
env: main: fun<main>, f: fun<f>, 
}
--- step exp main --->
{
stack: top{fun<main><-1> :: main()<0>}
heap: Int: x, fun<f>, fun<main>, 
env: main: fun<main>, f: fun<f>, 
}
--- handle value fun<main> with main()<1>(fun<main>,) --->
{
stack: top{()<-1> :: main()<1>(fun<main>,)}
heap: Int: x, fun<f>, fun<main>, 
env: main: fun<main>, f: fun<f>, 
}
--- step exp () --->
{
stack: top{()<-1> :: main()<1>(fun<main>,)}
heap: Int: x, fun<f>, fun<main>, 
env: main: fun<main>, f: fun<f>, 
}
--- handle value () with main()<2>(fun<main>,(),) --->
pattern_match((), ())
{
stack: main{var Int: a = 0; ... <-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 
env: main: fun<main>, f: fun<f>, 
}
--- step stmt var Int: a = 0; ...  --->
{
stack: main{var Int: a = 0;<-1> :: var Int: b = 1; ... <-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 
env: main: fun<main>, f: fun<f>, 
}
--- step stmt var Int: a = 0; --->
{
stack: main{0<-1> :: var Int: a = 0;<0> :: var Int: b = 1; ... <-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 
env: main: fun<main>, f: fun<f>, 
}
--- step exp 0 --->
{
stack: main{0<-1> :: var Int: a = 0;<0> :: var Int: b = 1; ... <-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 
env: main: fun<main>, f: fun<f>, 
}
--- handle value 0 with var Int: a = 0;<1>(0,) --->
{
stack: main{Int: a<-1> :: var Int: a = 0;<1>(0,) :: var Int: b = 1; ... <-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 
env: main: fun<main>, f: fun<f>, 
}
--- step exp Int: a --->
{
stack: main{Int<-1> :: Int: a<0> :: var Int: a = 0;<1>(0,) :: var Int: b = 1; ... <-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 
env: main: fun<main>, f: fun<f>, 
}
--- step exp Int --->
{
stack: main{Int<-1> :: Int: a<0> :: var Int: a = 0;<1>(0,) :: var Int: b = 1; ... <-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 
env: main: fun<main>, f: fun<f>, 
}
--- handle value Int with Int: a<1>(Int,) --->
{
stack: main{Int: a<-1> :: var Int: a = 0;<1>(0,) :: var Int: b = 1; ... <-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 
env: main: fun<main>, f: fun<f>, 
}
--- handle value Int: a with var Int: a = 0;<2>(0,Int: a,) --->
pattern_match(Int: a, 0)
{
stack: main{var Int: b = 1; ... <-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 0, 
env: a: 0, main: fun<main>, f: fun<f>, 
}
--- step stmt var Int: b = 1; ...  --->
{
stack: main{var Int: b = 1;<-1> :: f(0 = a); ... <-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 0, 
env: a: 0, main: fun<main>, f: fun<f>, 
}
--- step stmt var Int: b = 1; --->
{
stack: main{1<-1> :: var Int: b = 1;<0> :: f(0 = a); ... <-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 0, 
env: a: 0, main: fun<main>, f: fun<f>, 
}
--- step exp 1 --->
{
stack: main{1<-1> :: var Int: b = 1;<0> :: f(0 = a); ... <-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 0, 
env: a: 0, main: fun<main>, f: fun<f>, 
}
--- handle value 1 with var Int: b = 1;<1>(1,) --->
{
stack: main{Int: b<-1> :: var Int: b = 1;<1>(1,) :: f(0 = a); ... <-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 0, 
env: a: 0, main: fun<main>, f: fun<f>, 
}
--- step exp Int: b --->
{
stack: main{Int<-1> :: Int: b<0> :: var Int: b = 1;<1>(1,) :: f(0 = a); ... <-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 0, 
env: a: 0, main: fun<main>, f: fun<f>, 
}
--- step exp Int --->
{
stack: main{Int<-1> :: Int: b<0> :: var Int: b = 1;<1>(1,) :: f(0 = a); ... <-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 0, 
env: a: 0, main: fun<main>, f: fun<f>, 
}
--- handle value Int with Int: b<1>(Int,) --->
{
stack: main{Int: b<-1> :: var Int: b = 1;<1>(1,) :: f(0 = a); ... <-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 0, 
env: a: 0, main: fun<main>, f: fun<f>, 
}
--- handle value Int: b with var Int: b = 1;<2>(1,Int: b,) --->
pattern_match(Int: b, 1)
{
stack: main{f(0 = a); ... <-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 0, 1, 
env: b: 1, a: 0, main: fun<main>, f: fun<f>, 
}
--- step stmt f(0 = a); ...  --->
{
stack: main{f(0 = a);<-1> :: b = a; ... <-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 0, 1, 
env: b: 1, a: 0, main: fun<main>, f: fun<f>, 
}
--- step stmt f(0 = a); --->
{
stack: main{f(0 = a)<-1> :: f(0 = a);<-1> :: b = a; ... <-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 0, 1, 
env: b: 1, a: 0, main: fun<main>, f: fun<f>, 
}
--- step exp f(0 = a) --->
{
stack: main{f<-1> :: f(0 = a)<0> :: f(0 = a);<-1> :: b = a; ... <-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 0, 1, 
env: b: 1, a: 0, main: fun<main>, f: fun<f>, 
}
--- step exp f --->
{
stack: main{fun<f><-1> :: f(0 = a)<0> :: f(0 = a);<-1> :: b = a; ... <-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 0, 1, 
env: b: 1, a: 0, main: fun<main>, f: fun<f>, 
}
--- handle value fun<f> with f(0 = a)<1>(fun<f>,) --->
{
stack: main{(0 = a)<-1> :: f(0 = a)<1>(fun<f>,) :: f(0 = a);<-1> :: b = a; ... <-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 0, 1, 
env: b: 1, a: 0, main: fun<main>, f: fun<f>, 
}
--- step exp (0 = a) --->
{
stack: main{a<-1> :: (0 = a)<0> :: f(0 = a)<1>(fun<f>,) :: f(0 = a);<-1> :: b = a; ... <-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 0, 1, 
env: b: 1, a: 0, main: fun<main>, f: fun<f>, 
}
--- step exp a --->
{
stack: main{0<-1> :: (0 = a)<0> :: f(0 = a)<1>(fun<f>,) :: f(0 = a);<-1> :: b = a; ... <-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 0, 1, 
env: b: 1, a: 0, main: fun<main>, f: fun<f>, 
}
--- handle value 0 with (0 = a)<1>(0,) --->
{
stack: main{(0 = 0@5)<-1> :: f(0 = a)<1>(fun<f>,) :: f(0 = a);<-1> :: b = a; ... <-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 0, 1, 0, 
env: b: 1, a: 0, main: fun<main>, f: fun<f>, 
}
--- handle value (0 = 0@5) with f(0 = a)<2>(fun<f>,(0 = 0@5),) --->
pattern_match((0 = Int: x@0), (0 = 0@5))
pattern_match(Int: x, 0)
{
stack: f{return 0;<-1>} :: main{f(0 = a);<-1> :: b = a; ... <-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 0, 1, 0, 0, 
env: x: 0, main: fun<main>, f: fun<f>, 
}
--- step stmt return 0; --->
{
stack: f{0<-1> :: return 0;<0>} :: main{f(0 = a);<-1> :: b = a; ... <-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 0, 1, 0, 0, 
env: x: 0, main: fun<main>, f: fun<f>, 
}
--- step exp 0 --->
{
stack: f{0<-1> :: return 0;<0>} :: main{f(0 = a);<-1> :: b = a; ... <-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 0, 1, 0, 0, 
env: x: 0, main: fun<main>, f: fun<f>, 
}
--- handle value 0 with return 0;<1>(0,) --->
{
stack: main{0<-1> :: f(0 = a);<-1> :: b = a; ... <-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 0, 1, 0, !!0, 
env: b: 1, a: 0, main: fun<main>, f: fun<f>, 
}
--- handle value 0 with f(0 = a);<0>(0,) --->
{
stack: main{b = a; ... <-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 0, 1, 0, !!0, 
env: b: 1, a: 0, main: fun<main>, f: fun<f>, 
}
--- step stmt b = a; ...  --->
{
stack: main{b = a;<-1> :: return b;<-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 0, 1, 0, !!0, 
env: b: 1, a: 0, main: fun<main>, f: fun<f>, 
}
--- step stmt b = a; --->
{
stack: main{b<-1> :: b = a;<0> :: return b;<-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 0, 1, 0, !!0, 
env: b: 1, a: 0, main: fun<main>, f: fun<f>, 
}
--- step lvalue b --->
{
stack: main{ptr<4><-1> :: b = a;<0> :: return b;<-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 0, 1, 0, !!0, 
env: b: 1, a: 0, main: fun<main>, f: fun<f>, 
}
--- handle value ptr<4> with b = a;<1>(ptr<4>,) --->
{
stack: main{a<-1> :: b = a;<1>(ptr<4>,) :: return b;<-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 0, 1, 0, !!0, 
env: b: 1, a: 0, main: fun<main>, f: fun<f>, 
}
--- step exp a --->
{
stack: main{0<-1> :: b = a;<1>(ptr<4>,) :: return b;<-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 0, 1, 0, !!0, 
env: b: 1, a: 0, main: fun<main>, f: fun<f>, 
}
--- handle value 0 with b = a;<2>(ptr<4>,0,) --->
{
stack: main{return b;<-1>} :: top{}
heap: Int: x, fun<f>, fun<main>, 0, 0, 0, !!0, 
env: b: 0, a: 0, main: fun<main>, f: fun<f>, 
}
--- step stmt return b; --->
{
stack: main{b<-1> :: return b;<0>} :: top{}
heap: Int: x, fun<f>, fun<main>, 0, 0, 0, !!0, 
env: b: 0, a: 0, main: fun<main>, f: fun<f>, 
}
--- step exp b --->
{
stack: main{0<-1> :: return b;<0>} :: top{}
heap: Int: x, fun<f>, fun<main>, 0, 0, 0, !!0, 
env: b: 0, a: 0, main: fun<main>, f: fun<f>, 
}
--- handle value 0 with return b;<1>(0,) --->
{
stack: top{0<-1>}
heap: Int: x, fun<f>, fun<main>, !!0, !!0, !!0, !!0, 
env: main: fun<main>, f: fun<f>, 
}
result: 0