/* QUESTION 1 (5pts):

*

* You will implement a for-loop like construct, for_, using first-class

* functions.

*

* for_ takes 4 arguments:

*

* - cur: the initial current value

*

* - cond: the function that is used to decide whether or not we should

* execute the "loop" body. The cond function expects an argument whose type

* is the same as that of cur; the cond function is expected to return a

* boolean.

*

* - next: the function that is used to compute the "next" current value.

* Like cond, next expects an argument whose type is the same as that of cur;

* the next function is expected to return a value of the same type.

*

* - fbody: the function corresponding to the loop body. This function is

* called with the cur value as an argument.

*

* See examples/helpers-for-{1,2,3}.js for examples that demonstrate how to

* use for_ in place of for-loops. These files also describe the expected

* behavior of for_.

*/

function for_(cur, cond, next, fbody) {

/** **/

/** **/

}

exports.for_ = for_;

/* QUESTION 2 (5pts):

*

* Using the above for_ construct, you will now implement a construct for

* iterating over elements of an array. each takes a list and a function f. For

* each element in the list, the function calls f with the element and the

* index of the element in the list.

*/

function each(list, f) {

if (list.size == 0) {

return;

}

/** **/

/** **/

}

exports.each = each;

/* Below are some simple functionality tests.

* You may wish to test your code more extensively.

*/

{

let nr = 0; // track number of times function was e

each(List([1, 2, 3, 4, 5]), (el, idx) => {

nr++;

assert(el === idx + 1);

});

assert(nr === 5);

}

{

let nr = 0;

each(List([]), _ => { nr++; });

assert(nr === 0);

each(List([1]), _ => { nr++; });

assert(nr === 1);

}