<p>I've scoured the groovy doc and haven't found an analogue, but things there are organized a bit haphazardly. I'm switching from beanshell to groovy and was using the source("fileloc") method in beanshell to inline-include other, utility beanshell scripts for reuse. Is there a standard function to do this in groovy or a best practice?</p>

The reason you're not finding this is because Groovy is compiled.  Your Groovy code gets compiled into Java bytecode that gets run by the JVM right along side any Java code in your app.  This is why things like writing Groovified unit tests for large bodies of Java code requires zero extra effort.
The BeanShell is a Java-like
interpreted
language, so slurping in another got of code at run time is no big deal.
That said, you might be interested in
groovysh
and its
```
load
```
command.