<?xml version="1.0" standalone="yes"?>
<Paper uid="C92-2068">
  <Title>Quasi-Destructive Graph Unification with Structure-Sharing*</Title>
  <Section position="3" start_page="0" end_page="0" type="intro">
    <SectionTitle>
2 Namely.
</SectionTitle>
    <Paragraph position="0"> * Over Copying: Two dags ate created in order to create one new dag, This typically happens when Col)its of two input d~tgs are created prior to a destructive unific~Ltion operation to build one new dag.</Paragraph>
    <Paragraph position="1"> * Early Copying: Copies ar~ created prior to the failure of unification so that copies (:reltted since the beginning of the unitication up to the point of failure are wasted.</Paragraph>
    <Paragraph position="2"> Wroblewski defined Early Col)ying as follows: &amp;quot;The argutnent dags are copied be/t~te unification started. If the unilication fails then some of the Ct)l)ying is wasted effort&amp;quot; attd restricts early copying to cases that only apply to copies that are created prior to a unification. Our definition ()f Early Copying includes copies that ~rc created during a unification and created up t() the point of fltilur(~ width were iltt(!ow~red by Wroblewski's definition.</Paragraph>
  </Section>
class="xml-element"></Paper>