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Title: How to declare Linux variables by using newLisp
Post by: Darth_Severus on November 25, 2015, 09:17:38 AM

I'm able to run programs in Linux by using (! <name>) or (exec <name>). But I can't declare variables.

MAIN:/home/usernamedeleted> (! "declare final_answer=42")

sh: 1: declare: not found

32512

MAIN:/home/usernamedeleted> (! "set final_answer=42")

0

MAIN:/home/usernamedeleted> (! "echo $final_answer")

0

MAIN:/home/usernamedeleted> (! "final_answer=42")

0

MAIN:/home/usernamedeleted> (! "echo $final_answer")

0

MAIN:/home/usernamedeleted> (! "export final_answer=42")

0

MAIN:/home/usernamedeleted> (! "echo $final_answer")

0

MAIN:/home/usernamedeleted>

Title: Re: How to declare Linux variables by using newLisp
Post by: oofoe on November 25, 2015, 10:05:40 AM

Hi!

The "!" is a shell command -- it has its own environment every time it's run, which is not saved between invocations.

So, this:

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 (! "set final_answer=42")

is probably working, but when you run this:

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 (! "echo $final_answer")

the previous environment is destroyed in favour of the new one.

You can use the env function for this because it sets the variable in the environment of the currently running process -- newlisp itself:

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(env "final_answer" 42)
(! "echo $final_answer")

Hope this helps!

Title: Re: How to declare Linux variables by using newLisp
Post by: Darth_Severus on November 25, 2015, 11:37:23 AM

Ahh, that's it. Thanks!

But, the number needs to be a string as well.

Code Select Expand
(env "final_answer" "42")

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Forum => newLISP and the O.S. => Topic started by: Darth_Severus on November 25, 2015, 09:17:38 AM