How To Install happy on CentOS 7

In this tutorial we learn how to install happy on CentOS 7. happy is Parser Generator for Haskell

Introduction

In this tutorial we learn how to install happy on CentOS 7.

What is happy

Happy is a LALR(1) parser generator system for Haskell, similar to the tool yacc' for C. Like yacc’, it takes a file containing an annotated BNF specification of a grammar and produces a Haskell module containing a parser for the grammar. Happy is flexible program, and several entry points to a single grammar. Happy can work in conjunction with a lexical analyser supplied by the user (either hand-written or generated by another program).

We can use yum or dnf to install happy on CentOS 7. In this tutorial we discuss both methods but you only need to choose one of method to install happy.

Install happy on CentOS 7 Using yum

Update yum database with yum using the following command.

sudo yum makecache

After updating yum database, We can install happy using yum by running the following command:

sudo yum -y install happy

Install happy on CentOS 7 Using dnf

If you don’t have dnf installed you can install DNF on CentOS 7 first. Update yum database with dnf using the following command.

sudo dnf makecache

After updating yum database, We can install happy using dnf by running the following command:

sudo dnf -y install happy

How To Uninstall happy on CentOS 7

To uninstall only the happy package we can use the following command:

sudo dnf remove happy

References

Summary

In this tutorial we learn how to install happy on CentOS 7 using yum and dnf.