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>Metaprogramming itself is admittedly not ML's strength, though. Here I look up more to Racket's `syntax-parse`, which is both friendlier and more scalable than

>Metaprogramming itself is admittedly not ML's strength, though. Here I look up more to Racket's `syntax-parse`, which is both friendlier and more scalable than `defmacro`. ...No, not really. syntax-parse and defmacro are good at different things. While unhygenic macros are useless, procedural macros have their place. >unenforced conventions are just wishful thinking. Tell that to everyone developing java. :-). But one of the good things about lisp is that using syntactic extensions, we CAN enforce our own conventions. Just so long as you remember to unbind the native functions... >Actually, mutable objects, even objects whose class (not to be confused with type!) can change at runtime, are easy to implement in ML. The main reason why this programming style isn't as popular in ML-land is because it results in code that's harder to understand both for humans and for machines. Look, you're clearly a hardcore ML fan. You're not going to like Lisp. Lisp and ML are polar opposites of each other. Lisp is hyper-dynamic, ML is incredibly static. If you're the kind of person who can't last 5 minutes without typechecking and immutability guarantees, you'll either flee lisp quickly, or build your own bizarre ML inside of it.

catnaroek 10y ago
> syntax-parse and defmacro are good at different things. Yes, `syntax-parse` is good at being compositional - writing macros that don't step on each other's toes, just like normal functions. > Tell that to everyone developing java. :-). There's a reason why writing Java programs is so painful. The language is like a third world country's bureaucracy: it doesn't do anything useful by itself, and gets in the way of anyone who wants to do anything useful. > Look, you're clearly a hardcore ML fan. You're not going to like Lisp. It's not a matter of what I think. You said: “If it [Lisp] isn't the best at something, you can MAKE it the best.” All I did was give an example of something you can't make Lisp do. > Lisp is hyper-dynamic, ML is incredibly static. Every programming language has both static and dynamic parts. For example, lexical scope is intrinsically a static notion. And ML's exception construction is dynamic. The question is which particular combination of static and dynamic parts is most profitable for one's purposes. In any case, I really didn't want to turn this into a debate about types. My original objection was that Lisp doesn't have compound values. A dynamically typed language can have compound values.
- qwertyuiop924 10y ago
  >Yes, `syntax-parse` is good at being compositional - writing macros that don't step on each other's toes, just like normal functions. That's hygene. defmacro COULD have hygene, and indeed, some schemes provide ER macros, which are defmacro with hygene. What I was talking about was the fact that defmacro is imperative, and syntax-parse is declarative. The lack of hygene in defmacro is actually awful. >There's a reason why writing Java programs is so painful. The language is like a third world country's bureaucracy: it doesn't do anything useful by itself, and gets in the way of anyone who wants to do anything useful. I'll agree with that, but pretty much every java program out there is an example of guarantees maintained by the programmer, not the language. Not saying it's a good thing, am saying it's possible. >It's not a matter of what I think. You said: “If it [Lisp] isn't the best at something, you can MAKE it the best.” All I did was give an example of something you can't make Lisp do. Okay, but I didn't get it, because I'm still not sure what it was... >In any case, I really didn't want to turn this into a debate about types. My original objection was that Lisp doesn't have compound values. A dynamically typed language can have compound values. Do you mean ADTs? because if not, I'm not sure what you mean.
  - catnaroek 10y ago
    > Okay, but I didn't get it, because I'm still not sure what it was... Manipulate compound values directly! > Do you mean ADTs? because if not, I'm not sure what you mean. A compound value is built from simpler values. Examples of compound values include lists, trees, graphs, etc. To clarify, by “list”, I mean the actual sequence of elements, not object identity of the first cons cell.
    - qwertyuiop924 10y ago
      >Manipulate compound values directly! I fail to see how Lisp can't do this. What does set-cdr! do if not directly modify a cons cell, which is a compound value? what about hash-table-set! and vector-set!?
      - catnaroek 10y ago

catnaroek 10y ago

> syntax-parse and defmacro are good at different things. Yes, `syntax-parse` is good at being compositional - writing macros that don't step on each other's toes, just like normal functions. > Tell that to everyone developing java. :-). There's a reason why writing Java programs is so painful. The language is like a third world country's bureaucracy: it doesn't do anything useful by itself, and gets in the way of anyone who wants to do anything useful. > Look, you're clearly a hardcore ML fan. You're not going to like Lisp. It's not a matter of what I think. You said: “If it [Lisp] isn't the best at something, you can MAKE it the best.” All I did was give an example of something you can't make Lisp do. > Lisp is hyper-dynamic, ML is incredibly static. Every programming language has both static and dynamic parts. For example, lexical scope is intrinsically a static notion. And ML's exception construction is dynamic. The question is which particular combination of static and dynamic parts is most profitable for one's purposes. In any case, I really didn't want to turn this into a debate about types. My original objection was that Lisp doesn't have compound values. A dynamically typed language can have compound values.

qwertyuiop924 10y ago
>Yes, `syntax-parse` is good at being compositional - writing macros that don't step on each other's toes, just like normal functions. That's hygene. defmacro COULD have hygene, and indeed, some schemes provide ER macros, which are defmacro with hygene. What I was talking about was the fact that defmacro is imperative, and syntax-parse is declarative. The lack of hygene in defmacro is actually awful. >There's a reason why writing Java programs is so painful. The language is like a third world country's bureaucracy: it doesn't do anything useful by itself, and gets in the way of anyone who wants to do anything useful. I'll agree with that, but pretty much every java program out there is an example of guarantees maintained by the programmer, not the language. Not saying it's a good thing, am saying it's possible. >It's not a matter of what I think. You said: “If it [Lisp] isn't the best at something, you can MAKE it the best.” All I did was give an example of something you can't make Lisp do. Okay, but I didn't get it, because I'm still not sure what it was... >In any case, I really didn't want to turn this into a debate about types. My original objection was that Lisp doesn't have compound values. A dynamically typed language can have compound values. Do you mean ADTs? because if not, I'm not sure what you mean.
- catnaroek 10y ago
  > Okay, but I didn't get it, because I'm still not sure what it was... Manipulate compound values directly! > Do you mean ADTs? because if not, I'm not sure what you mean. A compound value is built from simpler values. Examples of compound values include lists, trees, graphs, etc. To clarify, by “list”, I mean the actual sequence of elements, not object identity of the first cons cell.
  - qwertyuiop924 10y ago
    >Manipulate compound values directly! I fail to see how Lisp can't do this. What does set-cdr! do if not directly modify a cons cell, which is a compound value? what about hash-table-set! and vector-set!?
    - catnaroek 10y ago