const regex = new RegExp('O\\s+(?P<O>\\d+\\.\\d+\\.\\d+\\.\\d+.*(?:[\\r\\n]+[^\\S\\r\\n]+.*)?)', 'mg')
const str = `Gateway of last resort is not set
10.0.1.0/8 is variably subnetted, 4 subnets, 2 masks
C 10.1.0.0/24 is directly connected, Ethernet1/0
L 10.1.0.1/32 is directly connected, Ethernet0/0
C 10.2.0.0/24 is directly connected, Ethernet0/1
L 19.18.2.1/32 is directly connected, Serial2/1
O 19.18.3.0/20 [110/128] via 19.18.2.2, 00:00:50, Serial1/1
[110/128] via 19.18.1.2, 00:00:50, Serial1/0
O 12.18.3.1/20 [110/128] via 19.18.2.2, 00:00:50, Serial1/1
[110/128] via 19.18.1.2, 00:00:50, Serial1/0
O 12.18.1.0/20 [110/128] via 19.18.2.2, 00:00:50, Serial0/1
[110/128] via 19.18.1.2, 00:00:50, Serial0/0`;
// 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