Discussion on: Daily Challenge #51 - Valid Curly Braces

const test = require('./tester');

const validateTCO = (acc, str) => (
    typeof str !== 'string'     ? false
    : str.length === 0          ? acc === 0
    : str.charAt(0) === '{'     ? validateTCO (acc + 1, str.slice(1))
    : str.charAt(0) === '}'     ? validateTCO (acc - 1, str.slice(1))
    : validateTCO (acc, str.slice(1))
);

const validate = str => validateTCO (0, str);

test (validate, [
    {
        in: ['{{}}'],
        out: true,
    },
    {
        in: ['{{{'],
        out: false,
    },
    {
        in: ['{}{}{}'],
        out: true,
    },
    {
        in: ['{abc {def} {{}}}'],
        out: true,
    },
]);