cleaned up error reporting in Read, and smallish message changes

Read.pm

@@ -39,13 +39,12 @@ sub end_file {
         undef($filename);
 }
 
-# after a read error, consume to end of line
+# after a read error, consume to end of line for the benefit of interactive use
 sub read_error {
         my ($in, $format, @args) = @_;
         <$in>;
         if ($filename) {
-                print STDERR ("\n\n$filename:$linecount: $format\n", @args);
-                error("in $filename");
+                error("\n\n$filename:$linecount: $format\n", @args);
         } else {
                 error($format, @args);
         }
@@ -57,7 +56,7 @@ sub Read {
         if (stringp($in)) {
                 my $string = $in;
                 open(my $str_in, "<", \$string) or
-                    error("read: cannot open string as filehandle: $!\n");
+                    error("read: cannot open string as filehandle: $!");
                 $in = $str_in;
         }
 
@@ -68,7 +67,7 @@ sub Read {
                 my $list = read_list_elems($in);
                 return undef unless defined($list);
                 my $closer = next_token($in);
-                return read_error($in, "syntax: list closed by $closer")
+                return read_error($in, "list closed by $closer")
                     unless $closer eq ')';
                 return $list;
         } elsif ($t eq '\'') {
@@ -78,11 +77,11 @@ sub Read {
                 return list(intern($Quote), $t);
         } elsif ($t eq '#\'') {
                 $t = Read($in);
-                return read_error($in, "EOF in quote")
+                return read_error($in, "EOF in #quote")
                     unless defined($t);
                 return list(intern($n_function), $t);
         } elsif ($t eq '.') {
-                return read_error($in, "found . where sexpr was expected");
+                return read_error($in, "found . when expecting sexpr");
         } elsif (symbolp($t)) {
                 return $t;
         } elsif ($t =~ m{^\"}) {
@@ -105,7 +104,7 @@ sub read_list_elems {
                         push_back_token($t);
                         return $list;
                 } elsif ($t eq '.') {
-                        return read_error($in, "syntax: . at start of list")
+                        return read_error($in, ". at start of list")
                             unless $end;
                         my $sexpr = Read($in);
                         return undef unless defined($t);
@@ -128,7 +127,7 @@ sub read_list_elems {
                         }
                 }
         }
-        return read_error($in, "EOF while reading list elements");
+        return read_error($in, "EOF reading list elements");
 }
 
 
@@ -211,7 +210,7 @@ sub error_or_eof {
         if (defined($!)) {
                 return read_error($in, "read failure: $!");
         }
-        return read_error($in, "unexpected EOF line");
+        return read_error($in, "unexpected EOF");
 }
 
 sub read_macro {