Here is the ramda function that accept a string parameter
const decodeBarcode => R.cond([
[x => R.equals(x.length, 12), decodeUPACBarcode],
[x => R.equals(x.length, 13), decode13DigitBarcode],
[x => R.gt(x.length, 20), decodeLengthGT20Barcode],
[R.T, R.identity],
]);
How to pass another parameter to improve condition?
another parameter barcodeType to be included
if (barcode.length > 20 or barcodeType = "DATAMATRIX")
Tried the below, not working !!
const decodeBarcode = (barcode, barcodeType) => R.cond([
[x => R.equals(x.length, 12), decodeUPACBarcode],
[x => R.equals(x.length, 13), decode13DigitBarcode],
[x => R.or(R.propEq('DATAMATRIX', barcodeType), R.gt(x.length, 20)), decodeLengthGT20Barcode],
[R.T, R.identity],
])(barcode);
You can use R.anyPass to run a list of predicates against a value, and return true is any of the predicate returns true:
const { cond, propEq, anyPass, propSatisfies, lte, T, identity } = R
const decodeLength13Barcode = () => console.log('Its 13 digit barcode')
const decodeLengthGT20Barcode = () => console.log('Its > 20 digit barcode')
const decodeBarcode = (barcode, barcodeType) => cond([
[propEq('length', 13), decodeLength13Barcode],
[anyPass([
propEq('DATAMATRIX', barcodeType),
propSatisfies(lte(20), 'length')
]), decodeLengthGT20Barcode],
[T, identity],
])(barcode);
console.log(decodeBarcode('0272889010009'));
console.log(decodeBarcode('02728890100099898989'));
console.log(decodeBarcode({ DATAMATRIX: '20d' }, '20d'));<script src="https://cdnjs.cloudflare.com/ajax/libs/ramda/0.28.0/ramda.min.js" integrity="sha512-t0vPcE8ynwIFovsylwUuLPIbdhDj6fav2prN9fEu/VYBupsmrmk9x43Hvnt+Mgn2h5YPSJOk7PMo9zIeGedD1A==" crossorigin="anonymous" referrerpolicy="no-referrer"></script>Since R.cond passes all parameters to the predicates, you can remove the arrow function (point-free). However, you pass bardcode, barcodeType, while R. propEq expects barcodeType, barcode, so you'll need to flip it after stating the property (DATAMATRIX):
const { cond, propEq, anyPass, flip, propSatisfies, lte, T, identity } = R
const decodeLength13Barcode = () => console.log('Its 13 digit barcode')
const decodeLengthGT20Barcode = () => console.log('Its > 20 digit barcode')
const decodeBarcode = cond([
[propEq('length', 13), decodeLength13Barcode],
[anyPass([
flip(propEq('DATAMATRIX')),
propSatisfies(lte(20), 'length')
]), decodeLengthGT20Barcode],
[T, identity],
]);
console.log(decodeBarcode('0272889010009'));
console.log(decodeBarcode('02728890100099898989'));
console.log(decodeBarcode({ DATAMATRIX: '20d' }, '20d'));<script src="https://cdnjs.cloudflare.com/ajax/libs/ramda/0.28.0/ramda.min.js" integrity="sha512-t0vPcE8ynwIFovsylwUuLPIbdhDj6fav2prN9fEu/VYBupsmrmk9x43Hvnt+Mgn2h5YPSJOk7PMo9zIeGedD1A==" crossorigin="anonymous" referrerpolicy="no-referrer"></script>If I understand correctly, you want something like this:
const decodeBarcode = cond ([
[propEq ('length', 12), decodeUPACBarcode],
[propEq ('length', 13), decode13DigitBarcode],
[(barcode, barcodeType) => barcode.length > 20 || barcodeType == "DATAMATRIX" , decodeLengthGT20Barcode],
[T, identity],
]);
const testCases = [
['123456789012', 'TYPEA'],
['1234567890123'],
['123456789012345678901'],
['12345678901234567', 'DATAMATRIX'],
['12345678901324567']
]
testCases .forEach (xs => console .log (
`decodeBarcode ('${xs .join(`', '`)}')\n//==> ${decodeBarcode (...xs)}`
)).as-console-wrapper {max-height: 100% !important; top: 0}<script src="//cdnjs.cloudflare.com/ajax/libs/ramda/0.28.0/ramda.min.js"></script>
<script>
const {cond, propEq, T, identity} = R
const decodeUPACBarcode = (barcode, type = '') => `calling decodeUPACBarcode('${barcode}', '${type}')`
const decode13DigitBarcode = (barcode, type = '') => `calling decode13DigitBarcode('${barcode}', '${type}')`
const decodeLengthGT20Barcode = (barcode, type = '') => `calling decodeLengthGT20Barcode('${barcode}', '${type}')`
</script>While we always have a way to make a function point-free, and it was worth doing for the first two conditions, the third one is going to be ugly enough that I wouldn't do it except as academic exercise. It might end up being something like this:
pipe (
unapply (zipWith (call) ([propSatisfies (gt (__, 20), 'length'), equals ('DATAMATRIX')])),
apply (or)
)
and that is much less readable than the arrow function currently used.