You should use -elide option on tags, not '-hidden'.
Look (Win32 command line): 
perl -MTk -we "for(tkinit->Text->pack){$_->tagConfigure('hidd',-elide=
+>1);$_->insert('end','x'x45,'','yyy','hidd');$_->update;sleep 1;$_->t
+agConfigure('hidd',-elide=>0);}MainLoop"

[download]
or even 
perl -MTcl::Tk=:perlTk -we "for(tkinit->Text->pack){$_->tagConfigure('
+hidd',-elide=>1);$_->insert('end','x'x45,'','yyy','hidd');update;slee
+p 1;$_->tagConfigure('hidd',-elide=>0);}MainLoop"

[download]

Courage, the Cowardly Dog
things, I do for love to perl...

In reply to Re: Tk: Make lines disappear in a Text widget? by Courage
in thread Tk: Make lines disappear in a Text widget? by bschmer

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