BTW, a easy explanation in how implement this for a language? I asked in https://www.reddit.com/r/ProgrammingLanguages/comments/9xsyad/how_provide_in_an_interp

BTW, a easy explanation in how implement this for a language? I asked in https://www.reddit.com/r/ProgrammingLanguages/comments/9xsyad/how_provide_in_an_interpreter_iteratosgenerators/ https://www.reddit.com/r/ProgrammingLanguages/comments/9xsya... and get a nice answer but is also of the style "just read this code and get it".