mtask.expr.tex

   1 Expressions in the \gls{mTask}-\gls{EDSL} are divided into two types, namely
   2 boolean expressions and arithmetic expressions. The class of arithmetic
   3 language constructs also contains the function \CI{lit} that lifts a
   4 host-language value into the \gls{EDSL} domain. All standard arithmetic
   5 functions are included in the \gls{EDSL} but are omitted in the example for
   6 brevity. Moreover, the class restrictions are only shown in the first functions
   7 and are omitted in subsequent functions. Both the boolean expression and
   8 arithmetic expression classes are shown in Listing~\ref{lst:arithbool}.
   9
  10 \begin{lstlisting}[language=Clean,label={lst:arithbool},
  11         caption={Basic classes for expressions}]
  12 class arith v where
  13   lit           :: t -> v t Expr
  14   (+.) infixl 6 :: (v t p) (v t q) -> v t Expr          | +, zero t    & isExpr p & isExpr q
  15   (-.) infixl 6 :: (v t p) (v t q) -> v t Expr          | -, zero t    & ...
  16   ...
  17 class boolExpr v where
  18   Not           :: (v Bool p) -> v Bool Expr            | ...
  19   (&.) infixr 3 :: (v Bool p) (v Bool q) -> v Bool Expr | ...
  20   ...
  21   (==.) infix 4 :: (v a p) (v a q) -> v Bool Expr       | ==, toCode a & ...
  22 \end{lstlisting}