I am a complete newbie at Perl. I have just started getting from bash to Perl language. I am trying to do a simple perl scripting that takes three arguments: two integers and an operation (+, -, * or /) and outputs the computed value.
Example:
$ ./perl_calc.pl 12 -13 *
-156
$
However, I don`t know how to turn that operation variable (+, -, * or /) back to an operation only, since when I put in $ARGV[0] $ARGV[1] $ARGV[1] they are all treated either as string or int.
Pls help me.
4  1464  KevinADC 4,059
Recognized Expert Specialist
Is this school work? Normally you would not eneter the math operators as arguments since they are treated as simple strings and have no functional purpose.
It belongs to the program of another course. I have just finish bash and wanted to learn some perl myself. However, looking for a simple solution through the webs is so difficult, since most of them only have difficult problems and tutorial texts, which couldn`t help me.
Can you help me out, pls?
KevinADC 4,059
Recognized Expert Specialist
eval is the perl funtion that turns strings/text into code. perldoc: eval function
But this is rarely something you would want to do in a real program. Allowing unvalidated user input to run as code is dangrous and extremely unwise.
Thank you very much for your help.
I know these codes are not pratical use. I just try to do some small perl code first
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