The code in this repository's purpose is to demonstrate how one might test an IO-heavy Haskell application w/out resorting to side-effectful operations.
This project was inspired by Sean Shubin's hello.
The program must do the following:
- take a command-line argument specifying the name of a file
- use that argument to read the contents of said file off disk
- prepend the string "hello " to the contents of the file
- print the aforementioned greeting (i.e. "hello martha") to the console
- print the number of milliseconds it took to complete steps 1-4 to the console
All examples rely on Stack by FP Complete. On a Mac, one can install Stack using Homebrew:
brew update
brew install haskell-stack
To build, install, and run the examples, look for run.sh and test.sh in the
root of each example-folder.
- (complete) using a type class
- using a data type
- (in progress) using a Operational monad