9 ms·

> in that case, pretend I wrote "grammarless" Gonna call you out on that as well. Forth, sure. Forth is...Forth. But Lisp is not grammarless. Smalltalk is not

> in that case, pretend I wrote "grammarless" Gonna call you out on that as well. Forth, sure. Forth is...Forth. But Lisp is not grammarless. Smalltalk is not either. The Lisp reader, notably Common Lisp, is a non-trivial piece of code. The Common Lisp lambda list, as a language construct, is not trivial either. (Dare I mention the CL LOOP macro?) Just because everything is "a list, symbol, or constant" does necessarily make the parsing problem trivial. It SEEMS simple, but then you get into it, and you find you fall into the weeds.

rewmie 3y ago
It seems those in this discussion arguing that they don't need a parser or a grammar simply aren't aware they're implementing ad-hoc parsers and grammars but doing it poorly.
- 082349872349872 3y ago
  Not only am I exactly aware of that, I am even advocating it. OP wants to write a hobby language, not reimplement Common Lisp. If OP wants sexprs, they can get quick-and-dirty sexprs by: (1) substituting spaces around each paren in the input (2) breaking input up into a list of whitespace separated words (3) folding over the resulting list (by looking at its parens) into a tree Sure, that's done poorly. However, it takes under 15 minutes (and under 15 lines?) to get them past their sticking point, and if the rest of their language (especially the part that differs from all other languages) actually turns out to be worth pursuing, they can always implement (or import) a real —or at least a better— reader later. See https://news.ycombinator.com/item?id=36593060 https://news.ycombinator.com/item?id=36593060
  - rewmie 3y ago
    > If OP wants sexprs, they can get quick-and-dirty sexprs by: You know what it takes to implement a parser for s expressions? E := atom | '(' *E ')' With atom expanding to all data types you wish to support. Let's presume using a parser generator is an insurmountable task for someone developing a parser. In a hand-rolled packrat parser, this whole grammar is implemented with a couple of functions. Is writing two functions too much work for someone wanting to write their own parser? Your ad-hoc trick is much more work than actually implementing a proper, maintainable parser.
    - carapace 3y ago
      FWIW, I've done it both ways. The ad-hoc trick is cromulent.

rewmie 3y ago

It seems those in this discussion arguing that they don't need a parser or a grammar simply aren't aware they're implementing ad-hoc parsers and grammars but doing it poorly.

082349872349872 3y ago
Not only am I exactly aware of that, I am even advocating it. OP wants to write a hobby language, not reimplement Common Lisp. If OP wants sexprs, they can get quick-and-dirty sexprs by: (1) substituting spaces around each paren in the input (2) breaking input up into a list of whitespace separated words (3) folding over the resulting list (by looking at its parens) into a tree Sure, that's done poorly. However, it takes under 15 minutes (and under 15 lines?) to get them past their sticking point, and if the rest of their language (especially the part that differs from all other languages) actually turns out to be worth pursuing, they can always implement (or import) a real —or at least a better— reader later. See https://news.ycombinator.com/item?id=36593060 https://news.ycombinator.com/item?id=36593060
- rewmie 3y ago
  > If OP wants sexprs, they can get quick-and-dirty sexprs by: You know what it takes to implement a parser for s expressions? E := atom | '(' *E ')' With atom expanding to all data types you wish to support. Let's presume using a parser generator is an insurmountable task for someone developing a parser. In a hand-rolled packrat parser, this whole grammar is implemented with a couple of functions. Is writing two functions too much work for someone wanting to write their own parser? Your ad-hoc trick is much more work than actually implementing a proper, maintainable parser.
  - carapace 3y ago
    FWIW, I've done it both ways. The ad-hoc trick is cromulent.