peek()
Get the most recently pushed context value.
pop()
Removes and returns the top context string from the stack.
contains($context)
Check if this context exists anywhere in the stack.
push($context)
Push a context onto the top of the stack.
toArray()
Get the entire context stack as an array (e.g.
fromArray(array $stack)
Overwrite the entire context stack from an array of strings.