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Move Pairs after Lists

stripped-german
Julian Ospald 9 years ago
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      VL1.tex

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VL1.tex View File

@@ -358,27 +358,10 @@ mod2 x
These \verb#|# things above are called \textbf{guards} and are similar to \emph{pattern matching}. They are processed in order. If the condition on the left side of the equation is true, then it returns what stands on the right side of the equation. If it's false, then it processes the next line.\\ \code{otherwise} on the last line is just defined as \code{True}, to make these constructs easier to read and catch all other cases of input.
\end{frame}

\section{7. Pairs/Tuples}
\section{7. Lists}

\begin{frame}[fragile]
\frametitle{7. Pairs/Tuples}
Defining a pair is easy.
\begin{haskellcode}
p :: (Int, Char) -- this is the type
p = (2, 'y') -- this is how we construct the pair

sumPair :: (Int, Int) -> Int
sumPair (x, y) = x + y
\end{haskellcode}
\pause
Note: we use \code{(x, y)} notation for both the type and the definition! Those are still two different things. We can also have triples, quadruples etc.
\end{frame}

\section{8. Lists}

\begin{frame}[fragile]
\frametitle{8. Lists}
\frametitle{7. Lists}
The list is probably the most basic data structure in Haskell. Like the array in C. It is a singly-linked list and is very lazy. The compiler has numerous ways to optimize lists, so don't be afraid to use them, even for huge things.
\pause
We build lists by using either the \code{[]} notation:
@@ -404,7 +387,7 @@ infiniteList = [1..]
\end{frame}

\begin{frame}[fragile]
\frametitle{8. Lists (ctn.)}
\frametitle{7. Lists (ctn.)}
Let's check on a few very common list operations:
\begin{haskellcode}
> [1, 2] ++ [4, 5] -- append two lists
@@ -427,7 +410,7 @@ A String in haskell is just a list of Chars!
\end{frame}

\begin{frame}[fragile]
\frametitle{8. Lists (ctn.)}
\frametitle{7. Lists (ctn.)}
Again, we can do pattern matching on lists.
\begin{haskellcode}
listLen :: [Integer] -> Integer
@@ -446,7 +429,7 @@ Note that \code{(x:(y:zs))} may also be written as \code{(x:y:zs)}.
\end{frame}

\begin{frame}[fragile]
\frametitle{8. Lists (ctn.)}
\frametitle{7. Lists (ctn.)}
Haskell also supports \textbf{list comprehension} which is basically syntactic sugar for what we already know from maths.\\
Let's define a set that contains the first ten even natural numbers:\\
\pause
@@ -467,6 +450,23 @@ Now let's say we want all numbers between 50 and 100 that have the remainder 0 w
\code{x <- [50..100]} is the binding, while \code{mod x 12 == 0} is the predicate, separated by a comma. We can have multiple predicates.
\end{frame}

\section{8. Pairs}

\begin{frame}[fragile]
\frametitle{8. Pairs}
Defining a pair is easy.
\begin{haskellcode}
p :: (Int, Char) -- this is the type
p = (2, 'y') -- this is how we construct the pair

-- pattern matching against pairs
sumPair :: (Int, Int) -> Int
sumPair (x, y) = x + y
\end{haskellcode}
\pause
Note: we use \code{(x, y)} notation for both the type and the definition! Those are still two different things. We can also have triples, quadruples etc.
\end{frame}

\section{9. Algebraic Data Types}

\begin{frame}[fragile]


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