const regex = /(?(DEFINE)
(?<n>[-+]?\d+(?:\.\d+)?)
(?<a>\s*[-+*\/]\s*)
(?<g>\((?:(?&n)|(?&g))(?&a)(?:(?&n)|(?&g))\))
)
^(?&g)$/gm;
// Alternative syntax using RegExp constructor
// const regex = new RegExp('(?(DEFINE)
(?<n>[-+]?\\d+(?:\\.\\d+)?)
(?<a>\\s*[-+*\\\/]\\s*)
(?<g>\\((?:(?&n)|(?&g))(?&a)(?:(?&n)|(?&g))\\))
)
^(?&g)$', 'gm')
const str = `(14.0 + 46.0)
((5.0 - 50.0) - 15.0)
(15.0 - (5.0 - 50.0))`;
// Reset `lastIndex` if this regex is defined globally
// regex.lastIndex = 0;
let m;
while ((m = regex.exec(str)) !== null) {
// This is necessary to avoid infinite loops with zero-width matches
if (m.index === regex.lastIndex) {
regex.lastIndex++;
}
// The result can be accessed through the `m`-variable.
m.forEach((match, groupIndex) => {
console.log(`Found match, group ${groupIndex}: ${match}`);
});
}
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions