comment:Basic test of the adjustable stack
push:ant
list
size
peek
pop
list
size
push:bat
list
size
peek
push:cow
push:dog
push:emu
list
size
peek
push:fox
list
size
peek
pop
list
size
peek
promote:dog
list
demote:cow
list
size
peek
depth:dog
depth:bat
depth:cow
depth:emu