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I never thought about this much but now and it has been so since Forth anyway: why are definitions prefix? Why do they not gobble up the stack? I always found

I never thought about this much but now and it has been so since Forth anyway: why are definitions prefix? Why do they not gobble up the stack? I always found it easier to create everything uniform like [0]. And I did that for many years with asm and c as well because I thought it was faster than porting something (it probably was not but he). I just like to minimize exceptions to rules and this seems a weird one to me. But probably has reasons I am unaware of (besides subjective readability which is, of course a very good reason). [0] https://gist.github.com/tluyben/16ee2645c4c8aed813005d51488d5c6a https://gist.github.com/tluyben/16ee2645c4c8aed813005d51488d...

retrac 5y ago
Yes, in my own toy concatenative language, define is just a regular procedure. It takes two arguments off the stack. The first is a pointer to the name, the second is a pointer to a quotation with the definition body. It intentionally looks Forth-like but it's different under the hood: [ dup + ] \ writes a lambda function to heap and push ptr : double ; \ : writes the next symbol as a string to heap and push ptr \ ; is define, writes definition into dict The reason Forth did it the classic Forth way originally, I suspect, is because Forth's parser needs to be told to switch modes. Stop executing words directly and start compiling them. There isn't really anywhere to store a temporary string, so you need to tell it to start writing into the dictionary entry before you give it the string. In my language, using [ ] for quotations starts writing to the heap, which is also where strings go. This has the same practical effect.
Skinney 5y ago
I agree in principle about the benefits of everything being uniform. For Stabel, specifically, I need some way of seperating function-definition from function-implementation, and a prefix meta language seemed like the best bet. Didn't look at it too closely, though.
- tluyben2 5y ago
  Thanks and, nice work with Stabel, we need more experiments in this space.

retrac 5y ago

Yes, in my own toy concatenative language, define is just a regular procedure. It takes two arguments off the stack. The first is a pointer to the name, the second is a pointer to a quotation with the definition body. It intentionally looks Forth-like but it's different under the hood: [ dup + ] \ writes a lambda function to heap and push ptr : double ; \ : writes the next symbol as a string to heap and push ptr \ ; is define, writes definition into dict The reason Forth did it the classic Forth way originally, I suspect, is because Forth's parser needs to be told to switch modes. Stop executing words directly and start compiling them. There isn't really anywhere to store a temporary string, so you need to tell it to start writing into the dictionary entry before you give it the string. In my language, using [ ] for quotations starts writing to the heap, which is also where strings go. This has the same practical effect.

Skinney 5y ago

I agree in principle about the benefits of everything being uniform. For Stabel, specifically, I need some way of seperating function-definition from function-implementation, and a prefix meta language seemed like the best bet. Didn't look at it too closely, though.

tluyben2 5y ago
Thanks and, nice work with Stabel, we need more experiments in this space.