X-Git-Url: https://git.stderr.nl/gitweb?p=matthijs%2Fmaster-project%2Fdsd-paper.git;a=blobdiff_plain;f=c%CE%BBash.lhs;h=6f158b5edc0b4e04357e51977bfb7a6ca8ab9e3f;hp=362fe5831c8679cd38292a76c03381bbf84456b6;hb=ff86fa7f14fb766248ff24849e3621674ba501e8;hpb=f513b84e02a6bd0215334379dda9b74a19d178ab diff --git "a/c\316\273ash.lhs" "b/c\316\273ash.lhs" index 362fe58..6f158b5 100644 --- "a/c\316\273ash.lhs" +++ "b/c\316\273ash.lhs" @@ -606,10 +606,7 @@ by an (optimizing) \VHDL\ synthesis tool. % against the constructors in the \hs{case} expressions. We can see two versions of a contrived example below, the first using a \hs{case} construct and the other using a \hs{if-then-else} - constructs, in the code below. The example sums two values when they are - equal or non-equal (depending on the predicate given) and returns 0 - otherwise. Both versions of the example roughly correspond to the same - netlist, which is depicted in \Cref{img:choice}. + constructs, in the code below. \begin{code} sumif pred a b = case pred of @@ -634,6 +631,11 @@ by an (optimizing) \VHDL\ synthesis tool. \caption{Choice - sumif} \label{img:choice} \end{figure} + + The example sums two values when they are equal or non-equal (depending on + the predicate given) and returns 0 otherwise. Both versions of the example + roughly correspond to the same netlist, which is depicted in + \Cref{img:choice}. A slightly more complex (but very powerful) form of choice is pattern matching. A function can be defined in multiple clauses, where each clause @@ -1153,7 +1155,7 @@ tools for formal verification. Lava descriptions are actually circuit generators when viewed from a synthesis viewpoint, in that the language elements of Haskell, such as choice, can be used to guide the circuit generation. If a developer wants to insert a choice element inside an actual -circuit he will have to specify this explicitly as a component. +circuit he will have to explicitly instantiate a multiplexer-like component. In this respect \CLaSH\ differs from Lava, in that all the choice elements, such as case-statements and pattern matching, are synthesized to choice @@ -1163,11 +1165,9 @@ mentioned in this section. The merits of polymorphic typing, combined with higher-order functions, are now also recognized in the `main-stream' hardware description languages, -exemplified by the new \VHDL-2008 standard~\cite{VHDL2008}. \VHDL-2008 has -support to specify types as generics, thus allowing a developer to describe +exemplified by the new \VHDL-2008 standard~\cite{VHDL2008}. \VHDL-2008 support for generics has been extended to types, allowing a developer to describe polymorphic components. Note that those types still require an explicit -generic map, whereas type-inference and type-specialization are implicit in -\CLaSH. +generic map, whereas types can be automatically inferred in \CLaSH. % Wired~\cite{Wired},, T-Ruby~\cite{T-Ruby}, Hydra~\cite{Hydra}. %