Expressions
An expression in Whistle evaluates to a value, this could be through either binary or unary expressions, or the special conditional expression.
In the future, once PR #21 gets merged, there will be a new type of expression: that of the array slice and index accessors.
Unary
A unary expression can be one of two things, either a primary or an operation. Due to the complexity and many different types of primary expressions the specification for them can be found here.
Operation
TODO
Binary
TODO
Conditional
TODO