prop-ops.js

// transform object's values
// given a object of functions and an object of value
// run object of values through object of functions
// matched by same prop name
export const map = (fieldFns = {} ) => obj => (
    Object.keys(obj)
        .reduce( (newObj, key) => {

            const fn = fieldFns[ key ];
            const originalValue = obj[ key ];

            return ({
                ...newObj,
                [ key ]: fn ? fn(originalValue) : originalValue
            });
        }, {})
);


// filter out some object props
// given a object of functions and an object of value
// run object of values through object of functions
// matched by same prop name
export const filter = (fieldFns = {}) => obj => (
    Object.keys(obj)
        .filter( key => fieldFns[key] ? fieldFns[key]( obj[key] ) : true )
        .reduce( (newObj, key) => ({...newObj, [key]: obj[key] }), {} )
);