regen/regcharclass.pl: Add ability for more complex inputs

This adds the capability to get input to this program from another
program, thus allowing essentially arbitrary input.

This will be used in future commits.

diff --git a/regen/regcharclass.pl b/regen/regcharclass.pl
index fb64ade..910953b 100755 (executable)
--- a/regen/regcharclass.pl
+++ b/regen/regcharclass.pl
@@ -362,6 +362,14 @@ sub new {
                 }
             }
             next;
+        } elsif ($str =~ / ^ do \s+ ( .* ) /x) {
+            die "do '$1' failed: $!$@" if ! do $1 or $@;
+            next;
+        } elsif ($str =~ / ^ & \s* ( .* ) /x) { # user-furnished sub() call
+            my @results = eval "$1";
+            die "eval '$1' failed: $@" if $@;
+            push @{$opt{txt}}, @results;
+            next;
         } else {
             die "Unparsable line: $txt\n";
         }
@@ -1071,10 +1079,21 @@ if ( !caller ) {
 #
 # The subsequent lines give what code points go into the class defined by the
 # macro.  Multiple characters may be specified via a string like "\x0D\x0A",
-# enclosed in quotes.  Otherwise the lines consist of single Unicode code
-# point, prefaced by 0x; or a single range of Unicode code points separated by
-# a minus (and optional space); or a single Unicode property specified in the
-# standard Perl form "\p{...}".
+# enclosed in quotes.  Otherwise the lines consist of one of:
+#   1)  a single Unicode code point, prefaced by 0x
+#   2)  a single range of Unicode code points separated by a minus (and
+#       optional space)
+#   3)  a single Unicode property specified in the standard Perl form
+#       "\p{...}"
+#   4)  a line like 'do path'.  This will do a 'do' on the file given by
+#       'path'.  It is assumed that this does nothing but load subroutines
+#       (See item 5 below).  The reason 'require path' is not used instead is
+#       because 'do' doesn't assume that path is in @INC.
+#   5)  a subroutine call
+#           &pkg::foo(arg1, ...)
+#       where pkg::foo was loaded by a 'do' line (item 4).  The subroutine
+#       returns an array of entries of forms like items 1-3 above.  This
+#       allows more complex inputs than achievable from the other input types.
 #
 # A blank line or one whose first non-blank character is '#' is a comment.
 # The definition of the macro is terminated by a line unlike those described.