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raganwald/javascript_generators_for_people_who_don’t_give_a_shit_about_gettingstuffdone™.es6

Last active March 14, 2021 07:13
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Revisions

  1. raganwald revised this gist May 15, 2016. No changes.
  2. raganwald revised this gist May 15, 2016. No changes.
  3. raganwald revised this gist May 15, 2016. No changes.
  4. raganwald revised this gist May 15, 2016. 1 changed file with 46 additions and 40 deletions.
    86 changes: 46 additions & 40 deletions javascript_generators_for_people_who_don’t_give_a_shit_about_gettingstuffdone™.es6
    View file
    Original file line number Diff line number Diff line change
    @@ -100,13 +100,23 @@ function * filterWith (fn, iterable) {
    }
    }

    function * primes (numbers = from(2)) {

    function * slices (length, iterable) {
    const iterator = iterable[Symbol.iterator]();
    let buffer = [...take(length, iterator)];

    if (buffer.length < length) return;

    let nextElementIndex = 0;

    while (true) {
    const { first, rest } = split(numbers);

    yield first;
    numbers = filterWith((n) => n % first !== 0, rest);
    yield buffer;

    const { value, done } = iterator.next();

    if (done) return;

    buffer = buffer.slice(1);
    buffer.push(value);
    }
    }

    @@ -120,26 +130,43 @@ const squares = mapWith((x) => x*x, from(1));

    const odds = filterWith((x) => x % 2 === 1, from(1));

    const reciprocals = mapWith((n) => 1/n, phi());
    function * primes (numbers = from(2)) {

    const fib = sequence2(0, 1, (x, y) => x + y);
    while (true) {
    const { first, rest } = split(numbers);

    yield first;
    numbers = filterWith((n) => n % first !== 0, rest);
    }
    }

    const greetings = mapWith(
    (x, y) => `${x} ${y}`,
    ['hello', 'bonjour', 'hej'],
    ['frank', 'pascal', 'rognvoldr']
    );

    const fibonacci = sequence2(0, 1, (x, y) => x + y);

    function * fibonacci () {
    function * fibonacci2 () {
    yield 0;
    yield 1;
    yield * mapWith(
    (x, y) => x + y,
    fibonacci(),
    rest(fibonacci())
    fibonacci2(),
    rest(fibonacci2())
    );
    }

    function * fibonacci3 () {
    yield 0;
    yield 1;
    yield * mapWith(
    ([x, y]) => x + y,
    slices(2, fibonacci3())
    );
    };

    function * phi () {
    yield * rest(
    mapWith(
    @@ -150,32 +177,11 @@ function * phi () {
    );
    }

    /////////////////////////////////////////////////////////////////
    /////////////////////////////////////////////////////////////////
    /////////////////////////////////////////////////////////////////
    /////////////////////////////////////////////////////////////////
    /////////////////////////////////////////////////////////////////

    console.log([...take(10, skit)])

    console.log([...take(10, from(42))])

    console.log([...take(10, sequence(2, (x) => x * 2))])

    console.log([...take(10, fibonacci())])

    console.log([...take(10, squares)])

    console.log([...take(10, odds)])

    console.log([...take(20, primes())])

    console.log([...greetings])

    console.log([...take(10, phi())])

    const squares2 = mapWith((x) => x*x, from(1));

    console.log([...take(10, reciprocals)])

    console.log([...take(10, fibonacci2)])
    function * phi2 () {
    yield * rest(
    mapWith(
    ([x, y]) => x / y,
    slices(2, fibonacci3())
    )
    );
    };
  5. raganwald revised this gist May 15, 2016. 1 changed file with 3 additions and 3 deletions.
    6 changes: 3 additions & 3 deletions javascript_generators_for_people_who_don’t_give_a_shit_about_gettingstuffdone™.es6
    View file
    Original file line number Diff line number Diff line change
    @@ -101,12 +101,12 @@ function * filterWith (fn, iterable) {
    }

    function * primes (numbers = from(2)) {

    while (true) {
    const { first, rest } = split(numbers);

    yield first;
    numbers = filterWith((n) => n % first !== 0, numbers);
    numbers = filterWith((n) => n % first !== 0, rest);
    }
    }

  6. raganwald revised this gist May 15, 2016. 1 changed file with 7 additions and 4 deletions.
    11 changes: 7 additions & 4 deletions javascript_generators_for_people_who_don’t_give_a_shit_about_gettingstuffdone™.es6
    View file
    Original file line number Diff line number Diff line change
    @@ -101,10 +101,13 @@ function * filterWith (fn, iterable) {
    }

    function * primes (numbers = from(2)) {
    const { first, rest } = split(numbers);

    yield first;
    yield * filterWith((n) => n % first !== 0, primes(rest));

    while (true) {
    const { first, rest } = split(numbers);

    yield first;
    numbers = filterWith((n) => n % first !== 0, numbers);
    }
    }

    // __Examples__
  7. raganwald revised this gist May 15, 2016. 1 changed file with 35 additions and 2 deletions.
    37 changes: 35 additions & 2 deletions javascript_generators_for_people_who_don’t_give_a_shit_about_gettingstuffdone™.es6
    View file
    Original file line number Diff line number Diff line change
    @@ -68,7 +68,6 @@ function * sequence2 (first, second, nextFn = (x, y) => y) {
    yield second;
    [first, second] = [second, nextFn(first, second)]
    }
    yield * join(first, sequence2(second, nextFn(first, second), nextFn));
    }

    function * mapWith (fn, ...iterables) {
    @@ -118,6 +117,10 @@ const squares = mapWith((x) => x*x, from(1));

    const odds = filterWith((x) => x % 2 === 1, from(1));

    const reciprocals = mapWith((n) => 1/n, phi());

    const fib = sequence2(0, 1, (x, y) => x + y);

    const greetings = mapWith(
    (x, y) => `${x} ${y}`,
    ['hello', 'bonjour', 'hej'],
    @@ -142,4 +145,34 @@ function * phi () {
    fibonacci()
    )
    );
    }
    }

    /////////////////////////////////////////////////////////////////
    /////////////////////////////////////////////////////////////////
    /////////////////////////////////////////////////////////////////
    /////////////////////////////////////////////////////////////////
    /////////////////////////////////////////////////////////////////

    console.log([...take(10, skit)])

    console.log([...take(10, from(42))])

    console.log([...take(10, sequence(2, (x) => x * 2))])

    console.log([...take(10, fibonacci())])

    console.log([...take(10, squares)])

    console.log([...take(10, odds)])

    console.log([...take(20, primes())])

    console.log([...greetings])

    console.log([...take(10, phi())])

    const squares2 = mapWith((x) => x*x, from(1));

    console.log([...take(10, reciprocals)])

    console.log([...take(10, fibonacci2)])
  8. raganwald revised this gist May 14, 2016. 1 changed file with 20 additions and 37 deletions.
    57 changes: 20 additions & 37 deletions javascript_generators_for_people_who_don’t_give_a_shit_about_gettingstuffdone™.es6
    View file
    Original file line number Diff line number Diff line change
    @@ -43,18 +43,31 @@ function * take (numberToTake, iterable) {
    }

    function * infiniteNumberOf (something) {
    yield * join(something, infiniteNumberOf(something));
    while (true) {
    yield something;
    }
    }

    function * from (first, increment = 1) {
    yield * join(first, from(first + increment, increment));
    function * from (number, increment = 1) {
    while (true) {
    yield number;
    number = number + increment;
    }
    }

    function * sequence (first, nextFn = (x) => x) {
    yield * join(first, sequence(nextFn(first), nextFn));
    function * sequence (value, nextFn = (x) => x) {
    while (true) {
    yield value;
    value = nextFn(value);
    }
    }

    function * sequence2 (first, second, nextFn = (x, y) => y) {
    yield first;
    while (true) {
    yield second;
    [first, second] = [second, nextFn(first, second)]
    }
    yield * join(first, sequence2(second, nextFn(first, second), nextFn));
    }

    @@ -105,7 +118,7 @@ const squares = mapWith((x) => x*x, from(1));

    const odds = filterWith((x) => x % 2 === 1, from(1));

    const greetings = zipWith(
    const greetings = mapWith(
    (x, y) => `${x} ${y}`,
    ['hello', 'bonjour', 'hej'],
    ['frank', 'pascal', 'rognvoldr']
    @@ -129,34 +142,4 @@ function * phi () {
    fibonacci()
    )
    );
    }

    /////////////////////////////////////////////////////////////////
    /////////////////////////////////////////////////////////////////
    /////////////////////////////////////////////////////////////////
    /////////////////////////////////////////////////////////////////
    /////////////////////////////////////////////////////////////////

    console.log([...take(10, skit)])

    console.log([...take(10, from(42))])

    console.log([...take(10, sequence(2, (x) => x * 2))])

    console.log([...take(10, fibonacci())])

    console.log([...take(10, squares)])

    console.log([...take(10, odds)])

    console.log([...take(20, primes())])

    console.log([...greetings])

    console.log([...take(10, phi())])

    const squares2 = zipWith((x) => x*x, from(1));

    const reciprocals = zipWith((n) => 1/n, phi());

    console.log([...take(10, reciprocals)])
    }
  9. raganwald revised this gist May 14, 2016. 1 changed file with 55 additions and 28 deletions.
    83 changes: 55 additions & 28 deletions javascript_generators_for_people_who_don’t_give_a_shit_about_gettingstuffdone™.es6
    View file
    Original file line number Diff line number Diff line change
    @@ -58,44 +58,41 @@ function * sequence2 (first, second, nextFn = (x, y) => y) {
    yield * join(first, sequence2(second, nextFn(first, second), nextFn));
    }

    function * mapWith (fn, iterable) {
    const asSplit = split(iterable);

    if (asSplit.hasOwnProperty('first')) {
    const { first, rest } = asSplit;
    function * mapWith (fn, ...iterables) {
    const iterators = iterables.map((iterable) => iterable[Symbol.iterator]());

    while (true) {
    const pairs = iterators.map((iterator) => iterator.next());
    const values = pairs.map((pair) => pair.value);
    const dones = pairs.map((pair) => pair.done);

    yield * join(fn(first),mapWith(fn, rest));
    if (dones.find((done) => done)) {
    return;
    } else {
    yield fn(...values);
    }
    }
    }

    function * filterWith (fn, iterable) {
    const asSplit = split(iterable);

    if (asSplit.hasOwnProperty('first')) {
    const { first, rest } = asSplit;

    if (fn(first)) {
    yield first;
    }
    yield * filterWith(fn, rest);
    }
    }
    const iterator = iterable[Symbol.iterator]();

    function * zipWith (fn, ...iterables) {
    const asSplits = iterables.map(split);

    if (asSplits.every((asSplit) => asSplit.hasOwnProperty('first'))) {
    const firsts = asSplits.map((asSplit) => asSplit.first);
    const rests = asSplits.map((asSplit) => asSplit.rest);
    while (true) {
    const { value, done } = iterator.next();

    yield * join(fn(...firsts), zipWith(fn, ...rests));
    if (done) {
    return;
    } else if (fn(value)) {
    yield value;
    }
    }
    }

    function * primes (numbers = from(2)) {
    const { first, rest } = split(numbers);

    yield * join(first, filterWith((n) => n % first !== 0, primes(rest)));
    yield first;
    yield * filterWith((n) => n % first !== 0, primes(rest));
    }

    // __Examples__
    @@ -117,7 +114,7 @@ const greetings = zipWith(
    function * fibonacci () {
    yield 0;
    yield 1;
    yield * zipWith(
    yield * mapWith(
    (x, y) => x + y,
    fibonacci(),
    rest(fibonacci())
    @@ -126,10 +123,40 @@ function * fibonacci () {

    function * phi () {
    yield * rest(
    zipWith(
    mapWith(
    (x, y) => x / y,
    rest(fibonacci()),
    fibonacci()
    )
    );
    }
    }

    /////////////////////////////////////////////////////////////////
    /////////////////////////////////////////////////////////////////
    /////////////////////////////////////////////////////////////////
    /////////////////////////////////////////////////////////////////
    /////////////////////////////////////////////////////////////////

    console.log([...take(10, skit)])

    console.log([...take(10, from(42))])

    console.log([...take(10, sequence(2, (x) => x * 2))])

    console.log([...take(10, fibonacci())])

    console.log([...take(10, squares)])

    console.log([...take(10, odds)])

    console.log([...take(20, primes())])

    console.log([...greetings])

    console.log([...take(10, phi())])

    const squares2 = zipWith((x) => x*x, from(1));

    const reciprocals = zipWith((n) => 1/n, phi());

    console.log([...take(10, reciprocals)])
  10. raganwald revised this gist May 9, 2016. 1 changed file with 40 additions and 5 deletions.
    45 changes: 40 additions & 5 deletions javascript_generators_for_people_who_don’t_give_a_shit_about_gettingstuffdone™.es6
    View file
    Original file line number Diff line number Diff line change
    @@ -81,20 +81,55 @@ function * filterWith (fn, iterable) {
    }
    }

    function * zipWith (fn, ...iterables) {
    const asSplits = iterables.map(split);

    if (asSplits.every((asSplit) => asSplit.hasOwnProperty('first'))) {
    const firsts = asSplits.map((asSplit) => asSplit.first);
    const rests = asSplits.map((asSplit) => asSplit.rest);

    yield * join(fn(...firsts), zipWith(fn, ...rests));
    }
    }

    function * primes (numbers = from(2)) {
    const { first, rest } = split(numbers);

    yield * join(first, filterWith((n) => n % first !== 0, primes(rest)));
    }

    // __Examples__

    const skit = infiniteNumberOf('spam');

    const powersOfTwo = sequence(2, (x) => x * 2);

    const fibonacci = sequence2(0, 1, (x, y) => x + y);

    const squares = mapWith((x) => x*x, from(1));

    const odds = filterWith((x) => x % 2 === 1, from(1));

    function * primes (numbers = from(2)) {
    const { first, rest } = split(numbers);
    const greetings = zipWith(
    (x, y) => `${x} ${y}`,
    ['hello', 'bonjour', 'hej'],
    ['frank', 'pascal', 'rognvoldr']
    );

    function * fibonacci () {
    yield 0;
    yield 1;
    yield * zipWith(
    (x, y) => x + y,
    fibonacci(),
    rest(fibonacci())
    );
    }

    yield * join(first, filterWith((n) => n % first !== 0, primes(rest)));
    function * phi () {
    yield * rest(
    zipWith(
    (x, y) => x / y,
    rest(fibonacci()),
    fibonacci()
    )
    );
    }
  11. raganwald revised this gist May 9, 2016. 1 changed file with 10 additions and 18 deletions.
    28 changes: 10 additions & 18 deletions javascript_generators_for_people_who_don’t_give_a_shit_about_gettingstuffdone™.es6
    View file
    Original file line number Diff line number Diff line change
    @@ -27,12 +27,8 @@ function split (iterable) {
    }
    };

    function * join (unjoined) {
    const {first, rest} = unjoined;

    if (unjoined.hasOwnProperty('first')) {
    yield first;
    }
    function * join (first, rest) {
    yield first;
    yield * rest;
    };

    @@ -47,22 +43,19 @@ function * take (numberToTake, iterable) {
    }

    function * infiniteNumberOf (something) {
    yield * join({
    first: something,
    rest: infiniteNumberOf(something)
    });
    yield * join(something, infiniteNumberOf(something));
    }

    function * from (first, increment = 1) {
    yield * join({first, rest: from(first + increment, increment)});
    yield * join(first, from(first + increment, increment));
    }

    function * sequence (first, nextFn = (x) => x) {
    yield * join({first, rest: sequence(nextFn(first), nextFn)});
    yield * join(first, sequence(nextFn(first), nextFn));
    }

    function * sequence2 (first, second, nextFn = (x, y) => y) {
    yield * join({first, rest: sequence2(second, nextFn(first, second), nextFn)});
    yield * join(first, sequence2(second, nextFn(first, second), nextFn));
    }

    function * mapWith (fn, iterable) {
    @@ -71,10 +64,7 @@ function * mapWith (fn, iterable) {
    if (asSplit.hasOwnProperty('first')) {
    const { first, rest } = asSplit;

    yield * join({
    first: fn(first),
    rest: mapWith(fn, rest)
    });
    yield * join(fn(first),mapWith(fn, rest));
    }
    }

    @@ -93,6 +83,8 @@ function * filterWith (fn, iterable) {

    // __Examples__

    const skit = infiniteNumberOf('spam');

    const powersOfTwo = sequence(2, (x) => x * 2);

    const fibonacci = sequence2(0, 1, (x, y) => x + y);
    @@ -104,5 +96,5 @@ const odds = filterWith((x) => x % 2 === 1, from(1));
    function * primes (numbers = from(2)) {
    const { first, rest } = split(numbers);

    yield * join({first, rest: filterWith((n) => n % first !== 0, rest)});
    yield * join(first, filterWith((n) => n % first !== 0, primes(rest)));
    }
  12. raganwald revised this gist May 9, 2016. 1 changed file with 38 additions and 19 deletions.
    57 changes: 38 additions & 19 deletions javascript_generators_for_people_who_don’t_give_a_shit_about_gettingstuffdone™.es6
    View file
    Original file line number Diff line number Diff line change
    @@ -18,15 +18,21 @@ function * rest (iterable) {

    function split (iterable) {
    const iterator = iterable[Symbol.iterator]();

    const { done, value: first } = iterator.next();
    if (!done) {

    if (done) {
    return { rest: [] };
    } else {
    return { first, rest: iterator };
    }
    };

    function * join (first, rest) {
    yield first;
    function * join (unjoined) {
    const {first, rest} = unjoined;

    if (unjoined.hasOwnProperty('first')) {
    yield first;
    }
    yield * rest;
    };

    @@ -41,34 +47,48 @@ function * take (numberToTake, iterable) {
    }

    function * infiniteNumberOf (something) {
    yield * join(something, infiniteNumberOf(something));
    yield * join({
    first: something,
    rest: infiniteNumberOf(something)
    });
    }

    function * from (first, increment = 1) {
    yield * join(first, from(first + increment, increment));
    yield * join({first, rest: from(first + increment, increment)});
    }

    function * sequence (first, nextFn = (x) => x) {
    yield * join(first, sequence(nextFn(first), nextFn));
    yield * join({first, rest: sequence(nextFn(first), nextFn)});
    }

    function * sequence2 (first, second, nextFn = (x, y) => y) {
    yield * join(first, sequence2(second, nextFn(first, second), nextFn));
    yield * join({first, rest: sequence2(second, nextFn(first, second), nextFn)});
    }

    function * mapWith (fn, iterable) {
    const { first, rest } = split(iterable);

    yield * join(fn(first), mapWith(fn, rest));
    const asSplit = split(iterable);

    if (asSplit.hasOwnProperty('first')) {
    const { first, rest } = asSplit;

    yield * join({
    first: fn(first),
    rest: mapWith(fn, rest)
    });
    }
    }

    function * filterWith (fn, iterable) {
    const { first, rest } = split(iterable);

    if (fn(first)) {
    yield first;
    const asSplit = split(iterable);

    if (asSplit.hasOwnProperty('first')) {
    const { first, rest } = asSplit;

    if (fn(first)) {
    yield first;
    }
    yield * filterWith(fn, rest);
    }
    yield * filterWith(fn, rest);
    }

    // __Examples__
    @@ -84,6 +104,5 @@ const odds = filterWith((x) => x % 2 === 1, from(1));
    function * primes (numbers = from(2)) {
    const { first, rest } = split(numbers);

    yield * join(first, filterWith((n) => n % first !== 0, rest));
    }

    yield * join({first, rest: filterWith((n) => n % first !== 0, rest)});
    }
  13. raganwald revised this gist May 9, 2016. 1 changed file with 6 additions and 19 deletions.
    25 changes: 6 additions & 19 deletions javascript_generators_for_people_who_don’t_give_a_shit_about_gettingstuffdone™.es6
    View file
    Original file line number Diff line number Diff line change
    @@ -57,31 +57,18 @@ function * sequence2 (first, second, nextFn = (x, y) => y) {
    }

    function * mapWith (fn, iterable) {
    const iterator = iterable[Symbol.iterator]();

    while (true) {
    const { done, value } = iterator.next();
    const { first, rest } = split(iterable);

    if (done) {
    return;
    }
    else yield fn(value);
    }
    yield * join(fn(first), mapWith(fn, rest));
    }

    function * filterWith (fn, iterable) {
    const iterator = iterable[Symbol.iterator]();

    while (true) {
    const { done, value } = iterator.next();
    const { first, rest } = split(iterable);

    if (done) {
    return;
    }
    else if (fn(value)) {
    yield value;
    }
    if (fn(first)) {
    yield first;
    }
    yield * filterWith(fn, rest);
    }

    // __Examples__
  14. raganwald revised this gist May 9, 2016. 1 changed file with 16 additions and 1 deletion.
    17 changes: 16 additions & 1 deletion javascript_generators_for_people_who_don’t_give_a_shit_about_gettingstuffdone™.es6
    View file
    Original file line number Diff line number Diff line change
    @@ -84,4 +84,19 @@ function * filterWith (fn, iterable) {
    }
    }

    // __Examples__
    // __Examples__

    const powersOfTwo = sequence(2, (x) => x * 2);

    const fibonacci = sequence2(0, 1, (x, y) => x + y);

    const squares = mapWith((x) => x*x, from(1));

    const odds = filterWith((x) => x % 2 === 1, from(1));

    function * primes (numbers = from(2)) {
    const { first, rest } = split(numbers);

    yield * join(first, filterWith((n) => n % first !== 0, rest));
    }

  15. raganwald created this gist May 9, 2016.
    87 changes: 87 additions & 0 deletions javascript_generators_for_people_who_don’t_give_a_shit_about_gettingstuffdone™.es6
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,87 @@
    function * just (...values) {
    yield * values;
    };

    function first (iterable) {
    const iterator = iterable[Symbol.iterator]();

    const { done, value } = iterator.next();
    if (!done) return value;
    };

    function * rest (iterable) {
    const iterator = iterable[Symbol.iterator]();

    iterator.next()
    yield * iterator;
    };

    function split (iterable) {
    const iterator = iterable[Symbol.iterator]();

    const { done, value: first } = iterator.next();
    if (!done) {
    return { first, rest: iterator };
    }
    };

    function * join (first, rest) {
    yield first;
    yield * rest;
    };

    function * take (numberToTake, iterable) {
    const iterator = iterable[Symbol.iterator]();

    for (let i = 0; i < numberToTake; ++i) {
    const { done, value } = iterator.next();
    if (done) return;
    else yield value;
    }
    }

    function * infiniteNumberOf (something) {
    yield * join(something, infiniteNumberOf(something));
    }

    function * from (first, increment = 1) {
    yield * join(first, from(first + increment, increment));
    }

    function * sequence (first, nextFn = (x) => x) {
    yield * join(first, sequence(nextFn(first), nextFn));
    }

    function * sequence2 (first, second, nextFn = (x, y) => y) {
    yield * join(first, sequence2(second, nextFn(first, second), nextFn));
    }

    function * mapWith (fn, iterable) {
    const iterator = iterable[Symbol.iterator]();

    while (true) {
    const { done, value } = iterator.next();

    if (done) {
    return;
    }
    else yield fn(value);
    }
    }

    function * filterWith (fn, iterable) {
    const iterator = iterable[Symbol.iterator]();

    while (true) {
    const { done, value } = iterator.next();

    if (done) {
    return;
    }
    else if (fn(value)) {
    yield value;
    }
    }
    }

    // __Examples__