Move length to multipurpose functions

lib/Minilisp.pm

@@ -227,20 +227,6 @@ my %stdctx = (
   'string-not-greaterp' => sub { my ($a, $b) = @_; return !(lc($a) gt lc($b)); },
   'string-not-lessp' => sub { my ($a, $b) = @_; return !(lc($a) lt lc($b)); },
 
-  # string length
-  'length' => sub {
-    my ($a) = @_;
-
-    if (ref($a) eq "ARRAY")
-      {
-        return scalar(@$a);
-      }
-    else
-      {
-        return length($a);
-      }
-  },
-
   # Bitwise operations
   'logand' => sub {
     my $v = -1;
@@ -312,6 +298,18 @@ my %stdctx = (
 
   # Multi-purpose
   'equal' => \&lisp_equal,
+  'length' => sub {
+    my ($a) = @_;
+
+    if (ref($a) eq "ARRAY")
+      {
+        return scalar(@$a);
+      }
+    else
+      {
+        return length($a);
+      }
+  },
 );
 
 sub parser {