Have tried it but no luck.
def isThreshold = eval("isThreshold1") generates this error.
groovy.lang.MissingMethodException: No signature of method: user_app_garyjmilne_Tile_Builder___Attribute_Monitor_1026.eval() is applicable for argument types: (org.codehaus.groovy.runtime.GStringImpl) values: [isThreshold1] Possible solutions: every(), equals(java.lang.Object), every(groovy.lang.Closure), each(groovy.lang.Closure), wait(), run() on line 1403 (method mainPage)