Templat:IsIPAddress
Returns 4 if the addres is IPv4, 6 if IPv6, and a blank when not an IP address.
Usage
sunting{{IsIPAddress|127.0.0.1}}
→ 4{{IsIPAddress|00AB:0002:3008:8CFD:00AB:0002:3008:8CFD}}
→ 6{{IsIPAddress|31poy}}
→{{IsIPAddress}}
→{{IsIPAddress|127.0.0.1}}
(opening with space) → 4
The blank can be distinguished in constructs like: {{#if:{{IsIPAddress|127.0.0.1}}|<!--yes-->|<!--no-->}}