multi line rules not working

[osmanfb1]

Hello,

I have cloned the fricas repository and built fricas (ubuntu  22.04.2). Seems to be working but when I tried multi line rules, I am getting a syntax error:

1) -> logrule1 := rule log a + log b == log(a*b)

   (1)  log(b) + log(a) + %B == log(a b) + %B
                       Type: RewriteRule(Integer,Integer,Expression(Integer))
(2) -> logrule1(log 2 + log 3)

   (2)  log(6)
                                                    Type: Expression(Integer)
(3) -> log 2 + log 3

   (3)  log(3) + log(2)
                                                    Type: Expression(Integer)
(4) -> logrule2 := rule
  Line   1: logrule2 := rule
           ............A
  Error  A: syntax error at top level
  Error  A: Improper syntax.
   2 error(s) parsing

(4) -> )version

Value = "FriCAS 2022-07-16 compiled at Thu Mar  2 03:01:13 PM EST 2023"

is this a known issue or am I doing something wrong??

Thanks

Osman

[Ralf Hemmecke]

> is this a known issue or am I doing something wrong??

I would call this a known issue.

But it is only for the default interface. It works fine if FriCAS reads
.input files or compiles .spad files.

There is a way to put FriCAS as a jupyter kernel and thus use the
Jupyter web interface. Since you know how to compile FriCAS, I could
make this available to you.
Or you use an older Version of FriCAS and follow the steps here:
https://hemmecke.github.io/qeta/fricasinstall.html

You can also consider to use FriCAS in emacs with the frimacs mode, then
you can write your multiline input into an .input file and send it to a
fricas session via Ctrl-C Ctrl-C.

https://github.com/pdo/frimacs

Or you can escape the end-of-line character by an underscore character.

(1) -> logrule2 := rule_
(log ( x ) + log ( y ) == log ( x * y );_
sin (x) * cos (y) == tan(x*y))

(I just added a stupid second rule for demonstration.) Then, however,
you need to put parentheses and separate by semicolon, because the
interpreter will basically read this as ONE long line.

Ralf

[osmanfb1]

Thanks for the quick reply Ralf. Emacs idea worked for me. But would be interested in getting the jupyter kernel too.

using underscores is also good. I was trying something like that using curly brackets :-(

Fricas/Axiom books or tutorials do not mention this at all. I built fricas with lisp only but it had the same problem

and was very slow (sbcl was the lisp). Built open-axiom , had the same problem.

Thanks again,

Osman