Re: Conca : a small interpreter
Jon Purdy <[email protected]> Tue, 29 Apr 2014 11:20:31 -0700
| Newsgroups | gmane.comp.lang.concatenative |
|---|---|
| Message-ID | <CAE3FWBtb+JTpZd3utCYu5pXUKhkTQa-nmmHWfDVC0t46hogKuA@mail.gmail.com> |
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> I was inspired by reading "The joy of Joy" and other things about concate=
native languages. Conca is an interpreter for a language like Joy and Cat.
This looks like a good project for learning about how concatenative
languages are put together.
> You will notice that Conca definitions are postfix like the rest of the l=
anguage. I could not think of a good reason to deviate from the postfix syn=
tax to handle definitions. Is there a technical reason Cat and Joy use some=
thing else?
Cat is statically typed, and it needs to know ahead of time what
definitions are available for type checking. I don=E2=80=99t know much abou=
t
Joy, but it doesn=E2=80=99t seem to have the same facility for mixing
compile-time and runtime evaluation that Forth does, so it seems
simpler to make =E2=80=9C=3D=3D=E2=80=9D just part of the syntax.
Since Conca is heavily dynamic, it makes sense to keep it consistently post=
fix.
> I am not sure how to deal with errors. Currently, Conca prints a message =
and skips the rest of the line. Should errors in a script be treated differ=
ently? So many choices to make. This is more complicted than I first though=
t. :-)
Error handling is a hard problem! You might implement an exception
system of some kind; it=E2=80=99s entirely up to you.
> I will read and consider comments. If there is interest, I may develop it=
further.
You should develop it further because of your own interest, not
because of other people=E2=80=99s. The question is: what problem do you wan=
t
Conca to solve? If you can answer that clearly, even if the answer is
=E2=80=9CI just want to write a programming language for fun=E2=80=9D, you =
will know
exactly what to do. :)
> P.S. Has interest in concatenative languages wanned in recent years?
The community is rather quiet, but fairly active. You should join
#concatenative on Freenode, where we talk about Factor and I post
updates about my own statically typed concatenative language project
called Kitten.
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<p>> I was inspired by reading "The joy of Joy" and othe=
r things about concatenative languages. Conca is an interpreter for a langu=
age like Joy and Cat.<br>
<br>
This looks like a good project for learning about how concatenative<br>
languages are put together.<br>
<br>
> You will notice that Conca definitions are postfix like the rest of th=
e language. I could not think of a good reason to deviate from the postfix =
syntax to handle definitions. Is there a technical reason Cat and Joy use s=
omething else?<br>
<br>
Cat is statically typed, and it needs to know ahead of time what<br>
definitions are available for type checking. I don=E2=80=99t know much abou=
t<br>
Joy, but it doesn=E2=80=99t seem to have the same facility for mixing<br>
compile-time and runtime evaluation that Forth does, so it seems<br>
simpler to make =E2=80=9C=3D=3D=E2=80=9D just part of the syntax.<br>
<br>
Since Conca is heavily dynamic, it makes sense to keep it consistently post=
fix.<br>
<br>
> I am not sure how to deal with errors. Currently, Conca prints a messa=
ge and skips the rest of the line. Should errors in a script be treated dif=
ferently? So many choices to make. This is more complicted than I first tho=
ught. :-)<br>
<br>
Error handling is a hard problem! You might implement an exception<br>
system of some kind; it=E2=80=99s entirely up to you.<br>
<br>
> I will read and consider comments. If there is interest, I may develop=
it further.<br>
<br>
You should develop it further because of your own interest, not<br>
because of other people=E2=80=99s. The question is: what problem do you wan=
t<br>
Conca to solve? If you can answer that clearly, even if the answer is<br>
=E2=80=9CI just want to write a programming language for fun=E2=80=9D, you =
will know<br>
exactly what to do. :)<br>
<br>
> P.S. Has interest in concatenative languages wanned in recent years?<b=
r>
<br>
The community is rather quiet, but fairly active. You should join<br>
#concatenative on Freenode, where we talk about Factor and I post<br>
updates about my own statically typed concatenative language project<br>
called Kitten.<br>
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