Expected or unexpected

Is there some default action undertaken when executing a Groovy script? 
I have the script:

        #! /usr/bin/env groovy
        
        expectedPrompts = [
                           "Enter length of first side: ",
                           "Enter length of second side: ",
                           "Enter length of third side: "
                           ]
        
which when executed produces:

        Exception in thread "main" java.lang.ClassFormatError: Invalid index 1 
in LocalVariableTable in class file testIt
                at java.lang.ClassLoader.defineClass1(Native Method)
                at java.lang.ClassLoader.defineClass(ClassLoader.java:620)
                at 
java.security.SecureClassLoader.defineClass(SecureClassLoader.java:124)
                at 
groovy.lang.GroovyClassLoader.access$100(GroovyClassLoader.java:81)
                at 
groovy.lang.GroovyClassLoader$ClassCollector.onClassNode(GroovyClassLoader.java:505)
                at 
groovy.lang.GroovyClassLoader$ClassCollector.call(GroovyClassLoader.java:515)
                at 
org.codehaus.groovy.control.CompilationUnit$5.call(CompilationUnit.java:604)
                at 
org.codehaus.groovy.control.CompilationUnit.applyToPrimaryClassNodes(CompilationUnit.java:844)
                at 
org.codehaus.groovy.control.CompilationUnit.classgen(CompilationUnit.java:540)
                at 
org.codehaus.groovy.control.CompilationUnit.compile(CompilationUnit.java:446)
                at 
groovy.lang.GroovyClassLoader.parseClass(GroovyClassLoader.java:244)
                at 
groovy.lang.GroovyClassLoader.parseClass(GroovyClassLoader.java:163)
                at groovy.lang.GroovyShell$2.run(GroovyShell.java:220)
                at java.security.AccessController.doPrivileged(Native Method)
                at groovy.lang.GroovyShell.run(GroovyShell.java:218)
                at groovy.lang.GroovyShell.run(GroovyShell.java:165)
                at groovy.ui.GroovyMain.processOnce(GroovyMain.java:385)
                at groovy.ui.GroovyMain.run(GroovyMain.java:251)
                at groovy.ui.GroovyMain.process(GroovyMain.java:234)
                at groovy.ui.GroovyMain.main(GroovyMain.java:136)
                at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
                at 
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
                at 
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
                at java.lang.reflect.Method.invoke(Method.java:585)
                at 
org.codehaus.classworlds.Launcher.launchStandard(Launcher.java:410)
                at org.codehaus.classworlds.Launcher.launch(Launcher.java:344)
                at org.codehaus.classworlds.Launcher.main(Launcher.java:461)

but if I add the line:

        expectedPrompts.each { println it }

after the list declaration then the script works fine.  I would have
thought a script with only a definition should execute correctly doing
nothing but...

-- 
Russel.
=============================================
Dr Russel Winder         +44 20 7585 2200
41 Buckmaster Road       +44 7770 465 077
London SW11 1EN, UK      russel-Q5fiE77zhxfe9xe1eoZjHA@xxxxxxxxxxxxxxxx

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