knifeblock: abstract away $nknives (nfc)

diff --git a/knifeblock-knives-filter b/knifeblock-knives-filter
index a5bee25d983ab825d8ca38ca539d6d08de3ce800..bb832cffc98bcd0016f20aef486bea2a23c3d120 100755 (executable)
--- a/knifeblock-knives-filter
+++ b/knifeblock-knives-filter
@@ -5,6 +5,8 @@ use POSIX;
 
 our %want;
 
+our $nknives = 3;
+
 our @part_order = qw(h b l);
 
 my $want = shift @ARGV;
@@ -12,9 +14,9 @@ my ($wknife,$wparts) = $want =~ m/^(\d)([a-z]+)$/ or die;
 
 sub want ($) {
     my ($colournum) = @_;
-    my $knife = ($colournum-1) % 3;
+    my $knife = ($colournum-1) % $nknives;
     return 0 unless $knife == $wknife;
-    my $part = $part_order[ floor(($colournum-1) / 3) ];
+    my $part = $part_order[ floor(($colournum-1) / $nknives) ];
     die "huh colour $colournum?" unless defined $part;
     return 0 unless $part =~ m/[$wparts]/o;
     print STDERR "$0: including colour $colournum ($knife $part)\n";