The Purpose of “<<” in Groovy

Instead of writing model.add(createModel(fileArgs.id,fileArgs.path,fileArgs.ext)) in groovy, there is a left shift operator, which can overload with double less than symbol model « createModel(fileArgs.id,fileArgs.path,fileArgs.ext)

resource: https://stackoverflow.com/questions/24818951/what-is-the-purpose-of-double-less-than-in-groovy/24819059#24819059