lucono/xtypejs — Gitpedia

Elegant, highly efficient data validation for JavaScript

Overview

Provides concise, performant, readable, data and type validation for JavaScript apps, using built-in and user-defined data-validating pseudo types.
Improves application efficiency and readability by unifying the most basic but common data and type validations in JavaScript apps, into single, concise, highly optimized operations.
Employs bitwise operations, data pre-processing, and memory-efficient memoization for fast, robust performance in small and large apps and libraries.
Ready for nodejs, requirejs, and regular script tag.
Website – xtype.js.org

Go from this:

js
function searchEmployees(value) {
    if (typeof value === 'string') {
         if (value.trim().length > 1) {
            return EmployeeDB.searchByName(value);
        } else if (value.trim().length === 1) {
            return EmployeeDB.searchByMiddleInitial(value);
        } else {
            return { error: 'Invalid search value supplied' };
        }
    } else if (typeof value === 'object' && value !== null) {
        if (Object.keys(value).length === 1) {
            return EmployeeDB.searchByFieldValuePair(value);
        } else if (Object.keys(value).length > 1) {
            return { error: 'Search by multiple fields not supported' };
        } else {
            return { error: 'Invalid search value supplied' };
        }
    } else if (typeof value === 'number') {
        if (!isNaN(value) && isFinite(value) && value > 0 && value % 1 === 0) {
            return EmployeeDB.searchByEmployeeNumber(value);
        } else {
            return { error: 'Invalid employee number supplied' };
        }
    } else if (typeof value === 'undefined' || value === null) {
        return { error: 'No search value supplied' };
    } else {
        return { error: 'Invalid search value supplied' };
    }
}

To concise, performant, readable, data validation:

js
function searchEmployees(value) {
    switch (xtype.which(value, 'str2+ str1 int+ obj1 obj2+ num nil')) {
        case 'str2+':
            return EmployeeDB.searchByName(value);
        case 'str1':
            return EmployeeDB.searchByMiddleInitial(value);
        case 'int+':
            return EmployeeDB.searchByEmployeeNumber(value);
        case 'obj1':
            return EmployeeDB.searchByFieldValuePair(value);
        case 'obj2+':
            return { error: 'Search by multiple fields not supported' };
        case 'num':
            return { error: 'Invalid employee number supplied' };
        case 'nil':
            return { error: 'No search value supplied' };
        default:
            return { error: 'Invalid search value supplied' };
    }
}

And even add custom validation types of your own:

js
xtype.ext.registerType('ssn', {
    validator: function(val) {
        return typeof val === 'string' && /^\d{3}-\d{2}-\d{4}$/.test(val);
    }
});

function searchEmployees(value) {
    switch (xtype.which(value, 'positive_integer, ssn, multi_char_string')) {
        case 'positive_integer':
            return EmployeeDB.searchByEmployeeNumber(value);
        case 'ssn':
            return EmployeeDB.searchBySSN(value);
        case 'multi_char_string':
            return EmployeeDB.searchByName(value);
        default:
            return { error: 'Invalid search value supplied' };
    }
}