abhishek-pawar / zippy

Zippy : File compression/decompression software in Haskell

Zippy

Zippy is a small file compression utility built purely in Haskell. It provides for two different data compression techniques, namely,

• Huffman Encoding
• Lempel–Ziv–Welch (LZW) Compression Algorithm

This project was built as a partial fullfilment towards CS2433-Principles of Programming Languages II (Spring'18) taught by Dr. Saurabh Joshi at IIT Hyderabad.

Getting Started

Running the application

Open a terminal window.

$ ./zippy <option> <input_file> <output_file>

Command-line Arguments

Zippy requires three command-line arguments : , <input_file> and <output_file>.

• <option> can take the following values:

  • -c-huf for compression using Huffman encoding.
  • -c-lzw for compression using LZW compression algorithm.
  • -d-huf for decompression using Huffman encoding.
  • -d-lzw for decompression using LZW compression algorithm.

• <input_file> is the relative path of the file to be compressed.

• <output_file> is the relative path of the compressed/decompressed file.

Building from source

Zippy requires GHC 8.0.2+ to build source. Clone the repository.

$ cd haskell-13
$ chmod +x build.sh
$ ./build.sh

Authors

• Pawar Abhishek Dwarkanath ([email protected])
• Ninad Akolekar ([email protected])
• Saahil Sirowa ([email protected])

zippy's Issues

Help option

We need to ignore (optionalize) the second and third arguments when using the --help flag. How do we do that?

Help text written in Help_option branch.

Module defined in multiple files Error

@ninadakolekar On compiling the main.hs file in lzw directory, I get the following error message:

<no location info>: error:
module ‘main:Main’ is defined in multiple files: lzw_main.hs
lzw_shared.hs
lzw_compress.hs
lzw_decompress.hs

Folder Compression in LZW

Folder has to be recursively compressed, maintaining a directory structure.
Currently, it gives error on input directory in LZW program.

@ssirowa

Parse/Syntax Errors in Compress File

@abhishekthelazy Some parse errors in compress module.