--- loncom/xml/run.pm	2000/06/28 19:52:20	1.2
+++ loncom/xml/run.pm	2001/07/20 21:19:38	1.18
@@ -1,13 +1,69 @@
 package Apache::run;
 
+sub evaluateold {
+  my ($expression,$safeeval,$decls) = @_;
+# print "inside2 evaluate $decls with $expression<br />\n";
+# gerd's old method interpolates unset vars
+# $safeeval->reval('return qq('.$expression.');');
+  unless (defined $expression) { return ''; }
+  my $result = '';
+  $@='';
+  $safeeval->reval('$_=q|'.$expression.'|;');
+  if ($@ eq '') {
+    $safeeval->reval('{'.$decls.'$_=~s/(\$[A-Za-z]\w*)/(defined(eval($1))?eval($1):$1)/ge;}');
+    if ($@ eq '') {
+      $result = $safeeval->reval('return $_;');
+    } else {
+      &Apache::lonxml::error("substitution on:$expression:with:$decls:caused");
+    }
+  } else {
+    &Apache::lonxml::error("defining:$expression:caused");
+  }
+  if ($@ ne '') {&Apache::lonxml::error($@);}
+  return $result
+}
+
+$Apache::run::EVALUATE_STRING=<<'ENDEVALUATE';  
+  my %oldexpressions=();
+  while (!$oldexpressions{$_}) {
+    $oldexpressions{$_}=1;
+    $_ =~s/((?:\$|\&)(?:[\#|\$]*[A-Za-z][\w]*|\{[A-Za-z][\w]*\}))([\[\{][^\$\&\]\}]+[\]\}])*?(\([^\$\&\)]+\))*?(?=[^\[\{\(]|$)/eval(defined(eval($1.$2))?eval('$1.$2.$3'):'$1.$2.$3')/seg;
+  }
+ENDEVALUATE
+
 sub evaluate {
-  my ($expression,$safeeval) = @_;
-  return $safeeval->reval($expression);
+  my ($expression,$safeeval,$decls) = @_;
+  unless (defined $expression) { return ''; }
+  if (!$Apache::lonxml::evaluate) { return $expression; }
+  my $result = '';
+  $@='';
+  $safeeval->reval('{'.$decls.';$_=<<\'EXPRESSION\';'."\n".$expression.
+		   "\n".'EXPRESSION'."\n".$EVALUATE_STRING.'}');
+#  $safeeval->reval('{'.$decls.';<< &evaluate(q|'.$expression.'|);}');
+  if ($@ eq '') {
+    $result = $safeeval->reval('return $_;');
+    chomp $result;
+  } else {
+    &Apache::lonxml::error("substitution on:$expression:with:$decls:caused $@");
+  }  
+  return $result
 }
 
 sub run {
-  my ($code,$safeeval) = @_;
-  $safeeval->reval($code);
+  my ($code,$safeeval,$hideerrors) = @_;
+#  print "inside run\n";
+  $@='';
+  my (@result)=$safeeval->reval($code);
+  if ($@ ne '' && !$hideerrors) {
+    &Apache::lonxml::error(":$code:caused");
+    &Apache::lonxml::error($@);
+  }
+  if ( $#result < '1') {
+    return $result[0];
+  } else {
+    &Apache::lonxml::debug("<b>Got lots results</b>:$#result:");
+    return (@result);
+  }
 }
 
 1;