Comments

diff --git a/lib/App/Scheme79asm.pm b/lib/App/Scheme79asm.pm
index e0bec36c64c32388335bd625fbacf63b36c6b0ed..c971c2cd2930905b25f284aef796d6934a135b6c 100644 (file)
--- a/lib/App/Scheme79asm.pm
+++ b/lib/App/Scheme79asm.pm
@@ -58,6 +58,8 @@ sub process {
        $addr = $self->process($addr) if ref $addr eq 'ARRAY';
        die 'Addr of toplevel is not atom: ', Dumper($addr), "\n" unless scalarp($addr);
 
+       my ($comment_type, $comment_addr) = ($type, $addr);
+
        unless (looks_like_number $addr) { # is symbol
                unless (exists $self->{symbols}{$addr}) {
                        $self->{symbols}{$addr} = $self->{nsymbols};
@@ -83,6 +85,7 @@ sub process {
                $location = $self->{freeptr}
        }
        $self->{memory}[$location] = $result;
+       $self->{comment}[$location] = "$comment_type $comment_addr";
        $location
 }
 
@@ -101,6 +104,7 @@ sub parse {
 sub finish {
        my ($self) = @_;
        $self->{memory}[5] = $self->{memory}[$self->{freeptr}];
+       $self->{comment}[5] = $self->{comment}[$self->{freeptr}];
        $self->{memory}[4] = $self->{freeptr};
        delete $self->{memory}[$self->{freeptr}]
 }
@@ -114,6 +118,7 @@ sub new {
        $args{symbols}{NIL} = 0;
        $args{symbols}{T} = 1;
        $args{nsymbols} = 2;
+       $args{comment} = ['(cdr part of NIL)', '(car part of NIL)', '(cdr part of T)', '(car part of T)', '(free storage pointer)', '', '(result of computation)'];
        bless \%args, $class
 }
 
@@ -122,14 +127,19 @@ sub print {
        $fh //= \*STDOUT;
 
        my $bits = $self->{type_bits} + $self->{addr_bits};
+       my $index_length = length $#{$self->{memory}};
+       my $index_format = '%' . $index_length . 'd';
        for my $index (0 .. $#{$self->{memory}}) {
                my $val = $self->{memory}[$index];
+               my $comment = $self->{comment}[$index];
                if ($index == 4) {
                        $val = "${bits}'d$val"
                } else {
                        $val = $val ? sprintf "%d'b%0${bits}b", $bits, $val : '0';
                }
-               say $fh "mem[$index] <= $val;"
+               my $spaces = ' ' x ($bits + 5 - (length $val));
+               $index = sprintf $index_format, $index;
+               say $fh "mem[$index] <= $val;$spaces // $comment"
        }
 }