ProgLang-HW1

group members

Yifan Li (liy42)

Ziqing Wang (wangz27)

Features/ bugs

There's no bug in our solutions.

We have 4 Reduction functions, and 4 helper functions.

Reduction Functions

function reducer is the reduce function called in Main function. It will reduce the lambda expression via alpha renaming, beta reduction or eta reduction

function alpha allows bound variable names in one lambda expression to be changed

function beta reduces one lambda expression by replacing the old String with a new lexp

function eta reduces one lambda expression by eta reduction: \x.(E x)->E

Helpter Functions

function helper is the helper function of function reducer, which checks break point and helps with reducer recursion

functions remove and freevars are used to find free variables in lambda expression, function getNewVar is used to rename a variable. These functions help alpha reduction.