more clearer , still avoid string-eval
#!/usr/bin/perl --
use strict; use warnings;
my $blah = q{-0.137 + (0.00479 / (W/0.9)) + (2.5593 * (W/0.9 ) ,0.045
+,0 };
print EvalPolynominal( $blah, 1,1 );
sub EvalPolynominal {
#first parameter gives the polynominal string
#second parameter gives the min-des width
#third parameter gives the short-line length
my $polynominal = shift;
my $curWidth = shift;
my $curLength = shift;
$polynominal =~ s/W/$curWidth/g ;#replace W with current value of
+min width
$polynominal =~ s/L/$curLength/g ;#replace L with current value of
+ min Length
local $@;
my $ret = eval $polynominal;
warn "Trying:\n\t$polynominal\nbut got: $@\n" if $@;
return $ret;
}
__END__
$ perl -we " -0.137 + (0.00479 / (1/0.9)) + (2.5593 * (1/0.9 ) ,0.045
+,0 "
syntax error at -e line 1, at EOF
Execution of -e aborted due to compilation errors.
$ perl blah
Trying:
-0.137 + (0.00479 / (1/0.9)) + (2.5593 * (1/0.9 ) ,0.045,0
but got: syntax error at (eval 1) line 2, at EOF
Use of uninitialized value in print at blah line 4.
$ perl -we " -0.137 + (0.00479 / (1/0.9)) + (2.5593 * (1/0.9 ) ,0.045
+,0 "
syntax error at -e line 1, at EOF
Execution of -e aborted due to compilation errors.
