Add comments about the cases in the if clause

pae2xml.pl

@@ -186,16 +186,16 @@ sub parse_notes {
   $notes =~ s/\=(\d)/$1/gs; # replace multibar rests #n with just n
 
   while ($notes ne "") {
-    if ($notes =~ /^(\'+|\,+)(.*)$/) {
+    if ($notes =~ /^(\'+|\,+)(.*)$/) {  # Octave marks
       ($oct, $notes) = ($1, $2);
       octave($oct);
-    } elsif ($notes =~ /^qq(.*)$/) {
+    } elsif ($notes =~ /^qq(.*)$/) {  # Begin grace
       $notes = $1;
       $qq = 1;
-    } elsif ($notes =~ /^r(.*)$/) {
+    } elsif ($notes =~ /^r(.*)$/) {  # End grace
       $notes = $1;
       $qq = 0;
-    } elsif ($notes =~ /^(\d+|\=)(\/.*)$/) {
+    } elsif ($notes =~ /^(\d+|\=)(\/.*)$/) {  # normal and multi-measure rests
       $measrest = $1;
       $notes = $2;
       if ($measrest eq '=') {
@@ -271,7 +271,7 @@ sub parse_notes {
 					<actual-notes>'.$act_notes.'</actual-notes>
 					<normal-notes>1</normal-notes>
 				</time-modification>', $qq);
-    } elsif ($notes =~ /^(%\w-\d)(.*)$/) {
+    } elsif ($notes =~ /^(%\w-\d)(.*)$/) {  # Clef change
       ($clef,$notes) = ($1,$2);
       $clef =~ /^%(\w)\-(\d)$/;
       ($clefsign, $clefline) = ($1, $2);
@@ -282,14 +282,14 @@ sub parse_notes {
 				</clef>
 			</attributes>
 ';
-    } elsif ($notes =~ /^@(\d\/\d|c\/?)\s*(.*)$/) {
+    } elsif ($notes =~ /^@(\d\/\d|c\/?)\s*(.*)$/) {  # time signatue change
       #	print "$notes\n";
       ($timesig,$notes) = ($1,$2);
       #print "-> $timesig / $notes\n"; exit;
       $timesig = timesignature($timesig);
       print OUT "			<attributes>\n$timesig
 			</attributes>\n";
-    } elsif ($notes =~ /^(:?\/+:?)(.*)$/) {
+    } elsif ($notes =~ /^(:?\/+:?)(.*)$/) {  # Barline (and repeats)
       $barline = $1;
       $notes = $2;
       if ($barline =~ /^:\/\/:/) {