About
+ +Copilot is a realtime programming language and Runtime Verification framework. +It allows users to write concise programs in a simple but powerful way using a +stream-based approach.
+ +Programs can be interpreted for testing, or translated C99 code to be +incorporated in a project, or as a standalone application. The C99 backend +ensures us that the output is constant in memory and time, making it suitable +for systems with hard realtime requirements. Copilot provides a strong type +system that helps keeping programmers from making common mistakes, aiding in +the quality of the code.
+ +Copilot provides a library providing higher-level constructs, for example for +defining clocks, a Boyer-Moore majority voting implementation and various +temporal logics, including Linear Temporal logic (LTL) and Past Time LTL.
+ +Code example
+ +This is a simple example showing basic usage. It implements a home heating +system: It heats when temp gets too low, and stops when it is high enough. It +reads temperature as a byte (range -50C to 100C) and translates this to +Celsius.
+ +{-# LANGUAGE RebindableSyntax #-}
+
+module Main where
+
+import Language.Copilot
+import Copilot.Compile.C99
+
+-- External temperature as a byte, range of -50C to 100C.
+temp :: Stream Word8
+temp = extern "temperature" Nothing
+
+-- Calculate temperature in Celsius.
+-- We need to cast the Word8 to a Float. Note that it is an unsafeCast, as there
+-- is no direct relation between Word8 and Float.
+ctemp :: Stream Float
+ctemp = (unsafeCast temp) * (150.0 / 255.0) - 50.0
+
+spec = do
+ -- Triggers that fire when the ctemp is too low or too high,
+ -- pass the current ctemp as an argument.
+ trigger "heaton" (ctemp < 18.0) [arg ctemp]
+ trigger "heatoff" (ctemp > 21.0) [arg ctemp]
+
+-- Compile the spec
+main = reify spec >>= compile "heater"