I've read similar ideas on Lisp. I don't put much stock in it in either context, but I think Lisp has a better claim to extensibility. All programming languages enable decomposition of a program. Functions/methods/macros/words don't really 'extend' a language.
You can't easily add garbage collection to Forth. You can't easily add static type-checking to Forth. Why call it 'extensible'? It's no more extensible than C.
It may be easier to hack on a Forth implementation than a C compiler, sure.
I've read similar ideas on Lisp. I don't put much stock in it in either context, but I think Lisp has a better claim to extensibility. All programming languages enable decomposition of a program. Functions/methods/macros/words don't really 'extend' a language.
You can't easily add garbage collection to Forth. You can't easily add static type-checking to Forth. Why call it 'extensible'? It's no more extensible than C.
It may be easier to hack on a Forth implementation than a C compiler, sure.