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?
You can assemble all the parts of your scripts into a String, then have a GroovyShell object evaluate your script. I picked this up from Venkat Subramanium's DSL examples.
part1 = new File("part1.groovy").text
part2 = new File("part2.groovy").text
script = """
println "starting execution"
${part1}
${part2}
println "done execution"
"""
new GroovyShell().evaluate(script)