q-lang-users

[q-lang-users] problem with command line parsing

[David M. <dah...@gm...>]

Hello Qusers,
With great travail I succeeded in compiling Q on my mac osx 10.3.4 system
(cannot upgrade because of unavailable ProTools drivers).  Q passed all of
it's internal tests, but the most elementary examples in the tutorials
return errors, for example:


==> sqr X = X*X;
sqr X=X*X

==> sqr 2
sqr 2

==> who


is my compilation broken or do I just not understand the syntax of the
language?

Re: [q-lang-users] problem with command line parsing

[Tim H. <q...@st...>]

"David Minor" <dah...@gm...> writes:

>    Hello Qusers,
>    With great travail I succeeded in compiling Q on my mac osx 10.3.4
>    system (cannot upgrade because of unavailable ProTools drivers).  Q
>    passed all of it's internal tests, but the most elementary examples in
>    the tutorials return errors, for example:
>    ==> sqr X = X*X;
>    sqr X=X*X
>    ==> sqr 2
>    sqr 2
>    ==> who
>    is my compilation broken or do I just not understand the syntax of the
>    language?

The latter. You don't define functions interactively; write scripts for
those. 


    #!/usr/local/bin/q
    #! -c main || quit

    sqr X = X*X;

    main = printf "%d\n" $ sqr 2 || quit;

gives:
 | zsh/scr9, potato 12:27PM temp/ % ./q.q
 | 4
 | zsh/scr9, potato 12:28PM temp/ %

HTH,

~Tim
-- 
<http://spodzone.org.uk/>

Re: [q-lang-users] problem with command line parsing

[Albert G. <Dr....@t-...>]

Hi David, and welcome to the list!

As Tim already pointed out, the interpreter only evaluates expressions,
so you need to put the equations into a file and run that with the
interpreter. The shebang magic and main function in Tim's example are
only needed, however, if you want to run your script as a standalone
program. Otherwise, just use your favourite text editor and put the line

sqr X = X*X;

into a file, say, sqr.q. Now you can run the program from the command
line like so:

q sqr.q

Or, if you already started the interpreter, you can run the script from
the interpreter's prompt:

==> run sqr.q

In any case, the equations are now ready to be used, so you can now type:

==> sqr 2

I should really put this into the FAQ, this has been asked a couple of
times already. :) However, you can find some information about using the
interpreter on the corresponding wiki page:

http://q-lang.wiki.sourceforge.net/Using+the+Interpreter

There you can also read about how to run the interpreter in Emacs, which
is maybe the most convenient way to run Q scripts interactively if you
know Emacs. I'm afraid that this information is a bit Linux-centric
right now, but the described setup should work equally well on OSX and
other Unix systems if you have Emacs installed.

BTW, in case you didn't know this, thanks to the work of Ryan Schmidt a
MacPorts port of Q to OSX exists which greatly reduces the hassle of
compiling Q there. You can find more information about this here:
http://q-lang.sourceforge.net/download.html#Ports

HTH,
Albert

-- 
Dr. Albert Gr"af
Dept. of Music-Informatics, University of Mainz, Germany
Email:  Dr....@t-..., ag...@mu...
WWW:    http://www.musikinformatik.uni-mainz.de/ag