This might be a domain-specific language (DSL). I pulled it from the GMC Inspire Designer
user manual. It's like C++/Java/C# but I don't think any of those has a function
keyword:
function stringIsLong(String Parameter1) : Bool
{
return Parameter1.Length > 20;
}
GMC Inspire runs on Windows and Linux, possibly under Mono, but I have no idea.
Reading deep in the PDF you provided the link for, there is a reference to developing DLLs in C or C#. I would guess that it is a slightly customised version of one of those.