Hi,
Can someone help me figure out how to do nested variable resolves and evaluation of numeric operations?
I am trying to make a system that stores formulas and variable values in an external file, and i want my perl script to pull in the values and the formulas, and then evaluate the formula with the variables having their values substituted into the formula. A small, representative, and problematic piece of code follows:
my $x = 3;
my $y = "2 * $x";
my $z = eval {$y};
print '$z is: ', $z, "\n";
print 'eval of $z is: ', eval{$z}, "\n";
print 'eval of "2 * 3" is: ', eval '2 * 3', "\n";
What I want is for the 2nd print statement to evaluate to the value '6', which the 3rd print statement does. Below is what I get:
$z is: 2 * 3
eval of $z is: 2 * 3
eval of "2 * 3" is: 6
Again, can someone help me figure out how to do nested variable resolves and evaluation of numeric operations?
Thanks,
Matt
Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
Read Where should I post X? if you're not absolutely sure you're posting in the right place.
Please read these before you post! —
Posts may use any of the Perl Monks Approved HTML tags:
- a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
| |
For: |
|
Use: |
| & | | & |
| < | | < |
| > | | > |
| [ | | [ |
| ] | | ] |
Link using PerlMonks shortcuts! What shortcuts can I use for linking?
See Writeup Formatting Tips and other pages linked from there for more info.