Jenkins samples groovy code vs plain groovy (closure errors) - jenkins

Question

In a jenkins shared library I can do something like this:
Jenkinsfile
#Library(value="my-shared-lib", changelog=false) _
jobGenerator {
notifier = [notifyEveryUnstableBuild: true]
}
sharedLibary/vars/jobGenerator.groovy
def call(body) {
println 'hi!'
}
To better understand the flow of whats goes on I have created two groovy files locally (with no reference to jenkins at all):
samples/launcher.groovy
jobGenerator {
s = 's'
}
samples/jobGenerator.groovy
def call(body) {
println 'inside jobGenerator '
}
But when I run that with:
groovy "/home/user/samples/launcher.groovy"
I get:
Caught: groovy.lang.MissingMethodException: No signature of method: launcher.jobGenerator() is applicable for argument types: (launcher$_run_closure1) values: [launcher$_run_closure1#61019f59]
groovy.lang.MissingMethodException: No signature of method: launcher.jobGenerator() is applicable for argument types: (launcher$_run_closure1) values: [launcher$_run_closure1#61019f59]
at launcher.run(launcher.groovy:2)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
So how much of the above code is jenkins/shared library specific? And is it even possible to write something like the above in plain groovy?
Or put in another way. How do I convert the above jenkins code to plain groovy?

Answer 1

IMHO following is close to what jenkins is doing
launcher.groovy
// load library scripts/functions
def binding = this.getBinding()
def gshell = new GroovyShell(this.getClass().getClassLoader(),binding)
new File("./my-lib").traverse(nameFilter: ~/.*\.groovy$/){f-> binding[f.name[0..-8]] = gshell.parse(f) }
// main
bar{
foo(name:"world")
}
./my-lib/foo.groovy
def call (Map m){
return "hello $m.name"
}
./my-lib/bar.groovy
def call (Closure c){
println ( "BAR: "+c() )
}
#> groovy launcher.groovy
BAR: hello world