FLP FUN RV-2-RKA

Author: xdusek21| Daniel Dušek

Project for class of Functional and Logic Programming Languages, Faculty of Information Technology, Brno University of Technology, 2017.

Content

• Usage
• Dependencies and compilation
• (Postfix) Regular expression to extended finite automaton algorithm
• Extension for automaton drawing
• Tests

Application rv-2-rka accepts on its input regular expression written in reverse polish notation and converts it to extended finite automaton.

Usage

rv-2-rka ((-r|--represent) | (-t|--transform)) [FILE]

-r | --represent reads from input file RE, converts it to internal representation and unchanged prints it back on standard output

-t | --transform reads from input file RE, converts it to EFA and prints the result on standard output

If no input file [FILE] is specified, standard input is read.

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Dependencies and compilation

For parameters and argument processing, optparse-applicative is used. To install the optparse-applicative, use cabal update && cabal install optparse-applicative.

If you are using linux distribution with GHC and GMake installed, it is possible to compile whole project using simple make command.

If you are using Microsoft Windows, you have to compile project by ghc Main.hs command.

Usage is same for both mentioned cases.

(Postfix) Regular Expression to Extended Finite Automaton Algorithm

Desribed in opory k předmětu TIN (in Czech). Implementation does not reduce resulting FA and leaves epsilon transitions.

Extension for automaton drawing

In my attempts to obtain bonus points for my project, I decided to implement extension that would allow to visualize resulting automaton. In order to do so, I implemented new switch -d | --transform-draw, which is used with the same syntax as switches -t|-r.

-d switch outputs LaTeX code which after translation in environment with tikz module available generates PDF containing resulting automaton.

By calling: ./rv-2-rka -d TestData/test.input.1.in > TestLatex.tex | pdflatex TestLatex.tex we can get file TestLatex.pdf in which there is visualized resulting automaton.

I wanted to avoid solution where I would have to run pdflatex from within haskell file itself which makes it harder to obtain the final image. That is solved in included Makefile, where there are several test-targets which will generate images to folder FSMImages:

make drawFSM-1  				# Generates image for  'a'
make drawFSM-2					# Generates image for  'ab.'
make drawFSM-3					# Generates image for RE from task assignment

make drawEverything				# All of the above in one shot!