jython-users

[Jython-users] Aargh! Jython and Readline

[Steve C. <St...@ig...>]

For about the third time, I have spent a few hours getting the readline
library worked into jython.  (It happens every time I install a new
jython and it changes a little bit each time.) You would think this
annoying mess would get documented somewhere, but it hasn't, anywhere,
correctly, in spite of several halfway attempts to do so.  And much of
the documentation is out of date.

So please, guys, make it a New Year's resolution to get this into the
official docs, somewhere.  Here is a start, it worked for me:


What you have to do to get Jython and Readline working (These
instructions work for GNUReadline on my RedHat Linux system - your
mileage may vary):=20

Note: there is another option called Editline but Bernhard Bablok, the
author of gnu java_readline says he couldn't get it working, so I didn't
even try.  Nonetheless, Editline is the default in jython according to
the source code in ReadlineConsole.java.  (See item #9 below ) If this
is going to be the case, then the jython docs should give more info
about it or work it into the standard distribution somehow. =20

1.  Download and install the javacc from
http://www.webgain.com/products/java_cc/.  You can't build jython
without this.

2.  Download the java-readline source from
http://www.bablokb.de/java/readline.html

3.  Make the java_readline jar and backing library using the Makefile
supplied.=20

4.  Deploy these into your system lib directory.  (/usr/lib in my case)

5.  Download the latest Jython sources from SourceForge. =20

6.  Create/Modify an ant.properties file in the same directory as the
build.xml for jython and add the property readline.jar giving it the
value of a path to the java_readline.jar you deployed in step 3,  as
well as the path to javacc and any other optional jars you wish to
include.

7.  Build jython and deploy it.

8.  Modify the jython shell script so as to precede the supplied command
(java -Dpython.home=3D...) with 'LD_LIBRARY_PATH=3D"/usr/lib"'

9.  Modify your registry file to add the line

     python.console.readlinelib=3DGnuReadline

As far as I know this one isn't documented anywhere and if you don't put
it in, the system tries to find Editline and throws an exception if it
can't. I only pieced it together from reading the source code for
jython's ReadlineConsole and for the gnu java readline.

After all that, you finally have a console that recognizes the arrow
keys for history when on the last line.  Way too complicated. =20

So while I thank the Jython developers and Mr. Bablok for their efforts
and for making this possible at all, please, someone, make this easier
or at least pull all the documentation into one place.

Re: [Jython-users] Aargh! Jython and Readline

[dman <ds...@ri...>]

On Sun, Dec 30, 2001 at 10:10:46AM -0600, Steve Cohen wrote:
| For about the third time, I have spent a few hours getting the readline
| library worked into jython.
...
| What you have to do to get Jython and Readline working (These
| instructions work for GNUReadline on my RedHat Linux system - your
| mileage may vary): 
...

Does it obey /etc/inputrc and ~/.inputrc for you?  The debian package
now includes the readline stuff (and depends on the java readline
package) but it doesn't have the vi keybindings (which I have
specified in both inputrc files).  bash and cpython (and other
programs, I am sure) obey the inputrc and give me the vi keybindings.

-D

-- 

Your beauty should not come from outward adornment, such as braided hair
and the wearing of gold jewelry and fine clothes.  Instead, it should be
that of your inner self, the unfading beauty of a gentle and quiet
spirit, which is of GREAT WORTH in God's sight.  For this is the way the
holy women of the past used to make themselves beautiful.
        I Peter 3:3-5

Re: [Jython-users] Aargh! Jython and Readline

[<bc...@wo...>]

[Steve Cohen]

>For about the third time, I have spent a few hours getting the readline
>library worked into jython.  (It happens every time I install a new
>jython and it changes a little bit each time.) You would think this
>annoying mess would get documented somewhere, but it hasn't, anywhere,
>correctly, in spite of several halfway attempts to do so.  And much of
>the documentation is out of date.
>
>So please, guys, make it a New Year's resolution to get this into the
>official docs, somewhere.  Here is a start, it worked for me:
>
>
>What you have to do to get Jython and Readline working (These
>instructions work for GNUReadline on my RedHat Linux system - your
>mileage may vary):=20
>
>Note: there is another option called Editline but Bernhard Bablok, the
>author of gnu java_readline says he couldn't get it working, so I didn't
>even try.  Nonetheless, Editline is the default in jython according to
>the source code in ReadlineConsole.java.  (See item #9 below ) If this
>is going to be the case, then the jython docs should give more info
>about it or work it into the standard distribution somehow. =20
>
>1.  Download and install the javacc from
>http://www.webgain.com/products/java_cc/.  You can't build jython
>without this.
>
>2.  Download the java-readline source from
>http://www.bablokb.de/java/readline.html
>
>3.  Make the java_readline jar and backing library using the Makefile
>supplied.=20
>
>4.  Deploy these into your system lib directory.  (/usr/lib in my case)
>
>5.  Download the latest Jython sources from SourceForge. =20
>
>6.  Create/Modify an ant.properties file in the same directory as the
>build.xml for jython and add the property readline.jar giving it the
>value of a path to the java_readline.jar you deployed in step 3,  as
>well as the path to javacc and any other optional jars you wish to
>include.
>
>7.  Build jython and deploy it.
>
>8.  Modify the jython shell script so as to precede the supplied command
>(java -Dpython.home=3D...) with 'LD_LIBRARY_PATH=3D"/usr/lib"'
>
>9.  Modify your registry file to add the line
>
>     python.console.readlinelib=3DGnuReadline
>
>As far as I know this one isn't documented anywhere and if you don't put
>it in, the system tries to find Editline and throws an exception if it
>can't. I only pieced it together from reading the source code for
>jython's ReadlineConsole and for the gnu java readline.

I think you have made it more difficult than you have to. To enable
readline you can use the binary distribution of jython-21b2, you just
have to set the registry options:

    python.console=org.python.util.ReadlineConsole
    python.console.readlinelib=GnuReadline

You still have to do items 2, 3, 4, 5 and 8, but I would rather not have
to document how because I have truely no clue about it.

The documentation for item 9 was missing, I have added a note about
python.console.readlinelib to the registry.html web-page.

    http://www.jython.org/docs/registry.html

Thank you for reporting the missing doc.

>After all that, you finally have a console that recognizes the arrow
>keys for history when on the last line.  Way too complicated.
>
>So while I thank the Jython developers and Mr. Bablok for their efforts
>and for making this possible at all, please, someone, make this easier
>or at least pull all the documentation into one place.

Sounds like a good candidate for a FAQ entry. Does anyone want to write
it up? The faqwizard is read-only at the moment but send the text to the
list, then I'll add it.

regards,
finn