jmaicaaan

const data = [
  1,
  2,
  3,
  4,
  5,
];

/**
 * 

jmaicaaan

const data = [
  1,
  2,
  3,
  4,
  5,
];

/**
 * 

jmaicaaan

const data = [
  1,
  2,
  3,
  4,
  5,
];

/**
 * 

jmaicaaan

const data = [
  1,
  2,
  3,
  4,
  5,
];

/**
 * 

jmaicaaan

// From here
const res = data
  .map(
    pipe(addBy1, multiplyBy2)
  )
  .filter(getItemsBelow10)
  .reduce(sum, 0)
  
  
  

jmaicaaan

/**
 * 
 * These utility functions are often available on various 
 * functional libraries (i.e ramdajs)
 * `compose` runs from right-to-left
 * `pipe` runs from left-to-right
 */
const compose = (...fns) => (initialValue) => fns.reduceRight((d, f) => f(d), initialValue);
const pipe = (...fns) => (initialValue) => fns.reduce((d, f) => f(d), initialValue);

jmaicaaan

const data = [
  1,
  2,
  3,
  4,
  5,
];

/**
 * 

jmaicaaan

const transducer = pipe(
  mapReduce(addBy1)(combinerConcat),
  mapReduce(multiplyBy2)(combinerConcat),
  filterReduce(getItemsBelow10)(combinerConcat)
);

const res = data
  .reduce(transducer, [])
  .reduce(sum, 0)
  

jmaicaaan

const mapReduce = mapperFn => combinerFn => (accumulator, currentValue) => {
  return combinerFn(accumulator, mapperFn(currentValue));
};

const filterReduce = predicateFn => combinerFn => (accumulator, currentValue) => {
  if (predicateFn(currentValue)) {
    return combinerFn(accumulator, currentValue);
  }
  return accumulator;
};

jmaicaaan

const data = [
  1,
  2,
  3,
  4,
  5,
];

/**
 *