I do not understand the error in the following sequence (modperl): 
my $nomSQL=$Nom;
if(undef($nomSQL)) { $nomSQL ="";}
$nomSQL =~ s/'/''/;

Use of uninitialized value in substitution (s///) at (...)/creat.pl line 33.
the "'" disappears, and I do not understand why after reading and rereading pelre, perlrequick and perlretut. The "'" is not special character?

Thank you in advance
Pierre Couderc

In reply to Why undefined? by pcouderc

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