Howto embed newlisp in (shell) programs?

[pjot]

Hi,

With Kornshell, it is easy to embed AWK and passing variables and vaules to the AWK program. It works as follows:

Code: Select all

STRING="Hello1 Hello2 Hello3"
awk -v VAR="$STRING" 'BEGIN {print VAR}'

This is a stupid example of course, but the idea is that you are able to pass values from a main program to a piece of AWK code.

Now, I want to do the same thing with newLisp. I have a main program in Kornshell and I want to pass some strings to a piece of newLisp code.

This line gives the same result as the AWK example just mentioned:

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newlisp -e "(silent (println \"Hello1 Hello2 Hello3\"))"

The question is, how do I pass the variable 'STRING' to the newlisp code? I thought of constructing the newLisp code as a string in advance, but it does not work:

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NEWLISP_LINE='(println \"${STRING}\")(exit)'
newlisp -e $NEWLISP_LINE

The result is

missing parenthesis : "...(println "

Also other constructions do not work:

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NEWLISP_LINE="(println $STRING)(exit)"
NEWLISP_LINE='(println $STRING)(exit)'

They all deliver the same error.

The workaround is to rewrite the main Kornshell program completely to newLisp, but then I have to convert over a 2000 lines of code. :-(

So, how can I embed newLisp code within a larger (shell) program, and pass values and variables to these codesnippets from the main program?

Thanks
Peter

[newdep]

Good point as I tried that also several times but its not very charming..

I you indeed would like to embed newLisp as it where Perl or Awk is
not very handy.. A thing i did once was making the code base64, but
that not readble ;-)

Would be very nice to have a way to simply embed newlisp in shell scripting
indeed... some extension to [text][/text].

like this should not complain about brackes etc...

$newlisp -e [text](sys-info)[/text]
-bash: syntax error near unexpected token `('

or

$newlisp -e {(sys-info)}

Should simply evaluate.. So actualy newlisp need a better parser on the command line ;-)

best would be directly ->

$newlisp -e (begin (sys-info))


Norman.

[newdep]

btw..its newlisp -e "(env {STRING})"

[pjot]

That does work on the command line but not in a program, unless exporting it explicitly:

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STRING="Hello1 Hello2 Hello3"
export STRING
newlisp -e "(env {STRING})"

But this works also, adding doublequotes:

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STRING="Hello1 Hello2 Hello3"
NEWLISP_LINE="(silent (println {$STRING}))"
newlisp -e "$NEWLISP_LINE"

Still it's a kind of clumsy...

[newdep]

I think i dont get it..this works inside bash..

#!/usr/bin/bash
STRING="Hello1 Hello2 Hello3"
awk -v VAR="$STRING" 'BEGIN {print VAR}'
newlisp -e "(0 6(env {STRING}))"

[newdep]

but this does not bring me what i want.. ;-)

#!/usr/bin/bash
STRING="Hello1 Hello2 Hello3"
awk -v VAR="$STRING" 'BEGIN {print VAR}'
newlisp -e "(env {STRING2} (string (0 6 (env {STRING}))))"
awk -v VAR="$STRING2" 'BEGIN {print VAR}'

and thats because we are dealing with a subshell issue..

[pjot]

I think i dont get it..this works inside bash..

#!/usr/bin/bash
STRING="Hello1 Hello2 Hello3"
awk -v VAR="$STRING" 'BEGIN {print VAR}'
newlisp -e "(0 6(env {STRING}))"

For me it doesn't... probably you still are in the same shell since the beginning, where you set the variable STRING on the prompt...?

If you start a new shell, does this piece of code still work?

[Lutz]

The question is, how do I pass the variable 'STRING' to the newlisp code?

like this:

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~> STRING="{Hello1 Hello2 Hello3}"
~> newlisp -e "(println $STRING)"
Hello1 Hello2 Hello3
"Hello1 Hello2 Hello3"

and this:

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NEWLISP='(silent (println "hello world"))'
~> newlisp -e "$NEWLISP"
hello world
~> 

[pjot]

That is not embedding newLisp in a shell program, that is starting newLisp from the command prompt.

So how do I pass a variable WITHIN a shell program?

You guys are setting the variable on the shell prompt, thereby automatically exporting it.

So, please start a new shell and copy and paste this into a new program.

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#!/bin/ksh
#
# Testing embedded newLisp
#
STRING="Hello1 Hello2 Hello3"
awk -v VAR="$STRING" 'BEGIN {print VAR}'
newlisp -e "(println $STRING)" 

Then exit your editor and run it with ksh, because it is a Kornshell program. (Other shells have the same problem, try with bash for example.) You'll see that AWK works, but that newLisp returns nil.

So, how do I pass the variable 'STRING' to the newlisp code within a larger shell program?

I can export it explicitly and use (env), or construct the newLisp code as a string in advance, but this is all kind of clumsy. But there seems to be no other way.

[Lutz]

ist works if you put an extra single quotes around the defintion of STRING, if not you get 3 nil's

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~> ./test
"Hello1 Hello2 Hello3"
Hello1 Hello2 Hello3
~> cat test
#!/bin/ksh
# 
# Testing embedded newLisp 
# 
STRING='"Hello1 Hello2 Hello3"' 
awk -v VAR="$STRING" 'BEGIN {print VAR}' 
newlisp -e "(silent (println $STRING ))"
~> 

I also tried with bin/bash, which also works. Remember that the shell expands literally into: (silent (println Hello1 Hello2 Hello3)) This is why we need the extra singgle quotes they make everhthinh inside the expansion: (silent (println "Hello1 Hello2 Hello3"))

[pjot]

That works!

The result is different (AWK has double quotes, newLisp hasn't) but that's ok, of course.

Thanks again!
Peter

[newdep]

Extra quotes?

You can use {} in newlisp... (advantage: the environment variable doesnt
have to be manipulated with extra quotes...)

#!/bin/bash
#
# Testing embedded newLisp
#
STRING="This can be anywhere"

awk -v VAR="$STRING" 'BEGIN {print "awk =>" VAR}'

newlisp -e "(silent (println {newlisp =>} {$STRING} ))"

STRING=ready?

newlisp -e "(silent (println {newlisp =>} {$STRING} ))"


STRING=10

newlisp -e "(silent (println (* 10 (int {$STRING})) ))"

[newdep]

even better.. but risky if you dont know the TYPE of the content of
the variable.. (Bash/ksh convert to string and Integer)


STRING=10

newlisp -e "(silent (println {newlisp =>} (* 10 $STRING) ))"

instead of

newlisp -e "(silent (println (* 10 (int {$STRING})) ))"


STRING=255

echo "bash =>" $(( 2 * STRING ))

echo "bash & newlisp =>" $(( STRING * `newlisp -e "$((STRING * STRING))"`))

echo "or like this =>" $(( STRING * `newlisp -e "(* 20 20)"` ))

echo "or =>" $(( 1024 * `newlisp -e $STRING`))

STRING=`newlisp -e "(div 22 7)"`

echo "newlisp again => " `newlisp -e "(silent (println (* $STRING 5)))"`


Get it ;-)