Normally this error occurs when the scalar you are performing the subsitution on has no content. So for example: 
my $tech;
$tech =~ s/a/b/;

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... will result in the error. To get around it you can do the following: 
my $tech;
$tech =~ s/a/b/ if defined $tech;

[download]
I hope that helps.

In reply to Re: Separating 'real' errors from ..err.. 'unreal'? by rpanman
in thread Separating 'real' errors from ..err.. 'unreal'? by ethrbunny

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