validation example with crocks js

validations.js

import('https://cdn.jsdelivr.net/npm/@esm-bundle/crocks/esm/index.js')
    .then(crocks => {
        const {
            Result,
            liftN,
            constant,
            identity,
            applyTo,
            defaultTo,
            map,
            ifElse
        } = crocks.default;


        const { Ok, Err } = Result;


        const buildValidator = (pred, errMessage) =>
            ifElse(pred,
                Ok,
                constant(Err([errMessage]))
            )


        const isLengthInRange = (min, max) => str => str.length > min && str.length < max
            ? Ok(str)
            : Err([`String needs to be in range ${min} | ${max}`])

        const stringIsShort = len => buildValidator(str => str.length >= len, 'string is to short')
        const stringIsLong = len => buildValidator(str => str.length <= len, 'string is to long')


        const isRequired = str => str ? Ok(str) : Err(['field is required'])

        const isValid = (validators = []) => value =>
            liftN(
                validators.length,
                identity,
                ...validators.map(
                    applyTo(value)
                )
            )

        // console.log(isValid([isRequired, isLengthInRange(4, 6)])('ssssw'))
        console.log(
            isRequired('sssssw')
                .chain(isValid([stringIsShort(3), stringIsLong(5)]))
        )
        // console.log(
        //     map(applyTo('ddd'),
        //         [isLengthInRange(4, 6), isRequired])
        // )


    })