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Strange behaviour in substitution

Strange behaviour in substitution

I am using this substitution to clean some inputted data.
I have used the same code numerous times before without problems.


$FieldValue = "Charlie----";
print "FVB - $FieldValue<br>";
$FieldValue = ~s/[^a-zA-Z0-9 \@\.]//gi;
print "FVA - $FieldValue<br><br>"; 

Gives output of:-


FVB - Charlie----
FVA - 18446744073709551615 

Why is it substituting the string for a number?


RE: Strange behaviour in substitution


Quote (man perlop)

Unary "~" performs bitwise negation, that is, 1's complement.
( man perlop | Symbolic Unary Operators )

Use the =~ operator instead :

CODE --> Perl(fragment)

$FieldValue =~ s/[^a-zA-Z0-9 \@\.]//gi; 


RE: Strange behaviour in substitution

I have been using that operator for years and never knew that.
All is working now - it is the simple things that catch me out.


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