Generator returns the generator that generated the file containing pos.

IsGenerated reports whether pos is in a generated file, It ignores //line directives.

IsMain reports whether the package being processed is a package main.

IsMainLike reports whether the package being processed is a main-like package.

IsMethod reports whether expr is a method call of a named method with signature meth.

MayHaveSideEffects reports whether expr may have side effects.