class BlueCloth

def self::flags_from_opthash( opthash={} )

## opthash), just return it as-is.
## Fixnum (e.g., if someone passed in an ORed flags argument instead of an
## Convert the specified +opthash+ into a flags bitmask. If it's already a 
def self::flags_from_opthash( opthash={} )
	return opthash if opthash.is_a?( Integer )
	# Support BlueCloth1-style options
	if opthash == :filter_html || opthash == [:filter_html]
		opthash = { :escape_html => true }
	elsif opthash == :filter_styles
		opthash = {}
	elsif !opthash.is_a?( Hash )
		raise ArgumentError, "option %p not supported" % [ opthash ]
	end
	flags = 0
	if   opthash[:remove_links]     then flags |= MKD_NOLINKS;         end
	if   opthash[:remove_images]    then flags |= MKD_NOIMAGE;         end
	if ! opthash[:smartypants]      then flags |= MKD_NOPANTS;         end
	if   opthash[:escape_html]      then flags |= MKD_NOHTML;          end
	if   opthash[:strict_mode]      then flags |= MKD_STRICT;          end
	if   opthash[:tagtext_mode]     then flags |= MKD_TAGTEXT;         end
	if ! opthash[:pseudoprotocols]  then flags |= MKD_NO_EXT;          end
	if   opthash[:xml_cdata]        then flags |= MKD_CDATA;           end
	if ! opthash[:superscript]      then flags |= MKD_NOSUPERSCRIPT;   end
	if ! opthash[:relaxed]          then flags |= MKD_NORELAXED;       end
	if ! opthash[:tables]           then flags |= MKD_NOTABLES;        end
	if ! opthash[:strikethrough]    then flags |= MKD_NOSTRIKETHROUGH; end
	if   opthash[:header_labels]    then flags |= MKD_TOC;             end
	if   opthash[:mdtest_1_compat]  then flags |= MKD_1_COMPAT;        end
	if   opthash[:auto_links]       then flags |= MKD_AUTOLINK;        end
	if   opthash[:safe_links]       then flags |= MKD_SAFELINK;        end
	if ! opthash[:pandoc_headers]   then flags |= MKD_NOHEADER;        end
	if   opthash[:expand_tabs]      then flags |= MKD_TABSTOP;         end
	if ! opthash[:divquotes]        then flags |= MKD_NODIVQUOTE;      end
	if ! opthash[:alphalists]       then flags |= MKD_NOALPHALIST;     end
	if ! opthash[:definition_lists] then flags |= MKD_NODLIST;         end
	if   opthash[:footnotes]        then flags |= MKD_EXTRA_FOOTNOTE;  end
	return flags
end