Yes, preprocessor is available as a standalone tool for preprocessing source files in assembly language (.S = input file before preprocessing, .s = output file

Yes, preprocessor is available as a standalone tool for preprocessing source files in assembly language (.S = input file before preprocessing, .s = output file after preprocessing or source file which does not require preprocessing). Of course standalone preprocessor can be (ab)used to preprocess Javascript source files and any other files, as grandparent commenter suggested.