This is a record of the output

./trivial
>> i = 10
>> print i 
10
>> i = i - i
>> print i 
0
>> i = 10
>> i = i - 1
>> print i 
9

arizotaz@Coltons-MacBook-Pro trivial_c++ % cat test.triv 
f = function(a) { return a * 2 }
print f(10)

i = 0
while (i < 3) {
    print i
    i = i + 1
}

if (1 > 0) { print 10 } else { print 1 }

arizotaz@Coltons-MacBook-Pro trivial_c++ % ./trivial test.triv 
20
0
1
2
10

arizotaz@Coltons-MacBook-Pro trivial_c++ % 