The utpl script language features a number of keywords which represent
certain special values.

-- Expect stdout --
The "this" keyword refers to the current function context: object
The "null" keyword represents the null value: null
The "true" keyword represents a true boolean value: true
The "false" keyword represents a false boolean value: false
-- End --

-- Testcase --
{% let t = { f: function() { return this; } } %}
The "this" keyword refers to the current function context: {{ type(t.f()) }}
The "null" keyword represents the null value: {{ "" + null }}
The "true" keyword represents a true boolean value: {{ true }}
The "false" keyword represents a false boolean value: {{ false }}
-- End --