From 73ae126c560b79464769b58668f7543f7c4734c0 Mon Sep 17 00:00:00 2001
From: Mart Lubbers <mart@martlubbers.net>
Date: Wed, 5 Jul 2017 17:14:20 +0200
Subject: [PATCH] embedding examples

---
 pres.mtask.tex | 128 ++++++++++++++++++++++++++++++++++++++++++-------
 1 file changed, 111 insertions(+), 17 deletions(-)

diff --git a/pres.mtask.tex b/pres.mtask.tex
index e0732f0..f878ecf 100644
--- a/pres.mtask.tex
+++ b/pres.mtask.tex
@@ -13,27 +13,122 @@
 	\end{itemize}
 \end{frame}
 
-\begin{frame}
-	\frametitle{Embedded Domain Specific Language (2)}
-	\framesubtitle{Embedding techniques}
-	\begin{block}{Deep}
-	\end{block}
+\begin{frame}[fragile]
+	\frametitle{Deep embedding}
+	\begin{columns}[t]
+		\column{.49\textwidth}
+		\begin{block}{What is deep embedding}
+			\begin{itemize}
+				\item The EDSL as an ADT
+				\item A view is a function transforming the ADT
+			\end{itemize}
+		\end{block}
+		\column{.49\textwidth}
+		\pause{}
+		\begin{lstlisting}
+:: DSL = LitI  Int     | LitB  Bool
+       | Var   String  | Plus  DSL DSL
+       | Minus DSL DSL | And   DSL DSL
+       | Eq    DSL
 
-	\begin{block}{Shallow}
+eval   :: DSL Env -> Env
+pprint :: DSL -> String
+		\end{lstlisting}
+	\end{columns}
+	\pause{}
+	\begin{block}{Properties}
+		\begin{itemize}
+			\item Easy to add views
+			\item Hard to extend
+			\item Not type safe
+			\pause\item GADT
+		\end{itemize}
 	\end{block}
+\end{frame}
+
+\begin{frame}[fragile]
+	\frametitle{Shallow embedding}
+	\begin{columns}[t]
+		\column{.49\textwidth}
+		\begin{block}{What is shallow embedding}
+			\begin{itemize}
+				\item The EDSL as a function
+				\item The view is embedded in the function
+			\end{itemize}
+		\end{block}
+		\pause{}
+		\column{.49\textwidth}
+		\begin{lstlisting}
+:: Env   = ...
+:: DSL a = DSL (Env -> a)
+
+Lit :: a -> DSL a
+Lit x = \e -> x
+
+Var :: String -> DSL Int
+Var i = \e -> retrEnv e i
 
-	\begin{block}{Class based shallow}
+Plus :: (DSL Int) (DSL Int) -> DSL Int
+Plus x y = \e -> x e + y e
+		\end{lstlisting}
+	\end{columns}
+	\pause{}
+	\begin{block}{Properties}
+		\begin{itemize}
+			\item Difficult to add views
+			\item Easy to extend
+			\item Type safe
+		\end{itemize}
 	\end{block}
 \end{frame}
 
-\begin{frame}
-	\frametitle{Embedded Domain Specific Language (2)}
-	\framesubtitle{Shallow Embedding}
-\end{frame}
+\begin{frame}[fragile]
+	\frametitle{Class based shallow embedding}
+	\begin{columns}[t]
+		\column{.49\textwidth}
+		\onslide<1->{
+			\begin{block}{The best of both worlds}
+				\begin{itemize}
+					\item The EDSL is a collection of classes
+					\item Views are types implementing a subset
+				\end{itemize}
+			\end{block}
+		}
+		\onslide<3->{
+			\begin{block}{Properties}
+				\begin{itemize}
+					\item Extendable
+					\item Type safe
+					\item Easy to add views
+				\end{itemize}
+			\end{block}
+		}
+		\column{.49\textwidth}
+		\begin{onlyenv}<2->
+			\begin{lstlisting}
+:: Env   = ...
+:: Evaluator a = Evaluator (Env -> a)
+:: PrettyPrinter a = PP String
 
-\begin{frame}
-	\frametitle{Embedded Domain Specific Language (3)}
-	\framesubtitle{Class Based Shallow Embedding}
+class intArith where
+	lit   :: t -> v t | toString t
+	add   :: (v t) (v t) -> (v t) | + t
+	minus :: (v t) (v t) -> (v t) | - t
+
+class boolArith where ...
+
+instance intArith Evaluator where
+	lit x   = Evaluator \e->x
+	add x y = Evaluator ...
+	...
+
+instance intArith PrettyPrinter where
+	lit x   = PP $ toString x
+	add x y = PP $ x +++ "+" +++ y
+	...
+			\end{lstlisting}
+		\end{onlyenv}
+	\end{columns}
 \end{frame}
 
 \subsection{mTask}
@@ -43,8 +138,7 @@
 	\begin{block}{What is mTask}
 		\begin{itemize}
 			\item EDSL
-			\item Generates C code
-			\item Arduino
+			\item Arduino C++ generation, iTasks simulation
 		\end{itemize}
 	\end{block}
 
@@ -55,7 +149,7 @@
 			\item Extendable
 			\item \ldots\pause{} but\ldots
 			\item No interaction
-			\item Compilation
+			\item Compilation requires reprogramming
 		\end{itemize}
 	\end{block}
 \end{frame}
-- 
2.20.1