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<DIV><FONT size=2>Hello together,</FONT></DIV>
<DIV> </DIV>
<DIV><FONT size=2>I hope you forgive this newbie question from</FONT><FONT
size=2> a C++, Perl, etc.</FONT></DIV>
<DIV><FONT size=2>geek who is willing to convert to Erlang</FONT><FONT size=2>
in order to set up a</FONT></DIV>
<DIV><FONT size=2>fault-tolerant and distributed system</FONT><FONT size=2>
without having to write</FONT></DIV>
<DIV><FONT size=2>base classes for the next 5 years ....</FONT></DIV>
<DIV> </DIV>
<DIV><FONT size=2>The question is about data structures and the copy
overhead</FONT></DIV>
<DIV><FONT size=2>of their modification.</FONT></DIV>
<DIV><FONT size=2>Let's say you have in Perl something like</FONT><FONT
size=2></FONT></DIV>
<DIV><FONT size=2> $record = {</FONT><FONT
size=2></FONT></DIV>
<DIV><FONT size=2>
"language" => 'Java'</FONT><FONT size=2>,</FONT></DIV>
<DIV><FONT size=2>
"status" => 'overhyped',</FONT></DIV>
<DIV><FONT size=2>
"usage" => 'with care',</FONT></DIV>
<DIV><FONT
size=2>
"samples" => [ $prog1,</FONT><FONT size=2> $prog2 ]
%% each $progX is a 200kByte data chunk</FONT></DIV>
<DIV><FONT size=2> }</FONT></DIV>
<DIV><FONT size=2>Now, how do I most effeciently do something like</FONT></DIV>
<DIV><FONT size=2> $record->{status} =
"dead".</FONT></DIV>
<DIV> </DIV>
<DIV><FONT size=2>So to put it simple: how do I update large data structures
without</FONT></DIV>
<DIV><FONT size=2>running into useless copy operations of the whole
structure.</FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2>I assume that Erlang is handling these matters as
elegantly as it</FONT></DIV>
<DIV><FONT size=2>handles the rest of the world, but being suspicious by nature
it would</FONT></DIV>
<DIV><FONT size=2>make me sleep better if I get tons of replies like 'Hey silly
newbie, this is simple ....'.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT size=2>Thanks in advance ...</FONT></DIV>
<DIV> </DIV>
<DIV><FONT size=2>With best regards</FONT></DIV>
<DIV> </DIV>
<DIV><FONT size=2>Eberhard Lutz</FONT></DIV>
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