On Sep 19, 2008, at 2:05 PM, Sergiu Dumitriu wrote: This would be the definition (as described in the creole link I mentioned): <#ESCAPE: ( "~" ~[" ", "\t", "\n", "\r"] ) > The reason to choose ~ is because it's not a character you use often (certainly less often than \ IMO). From the creole link: " Rationale: If one needs keyboard characters often in a text, there would be too many distracting triple curly braces to be able to work with the text well. Therefore an escape character would help to keep people from being so distracted by the nowiki inline and escape character could be used instead. The tilde was chosen, so it would not conflict with the backslashes in line breaks and because it is a relatively infrequently used character. It is not generally easy to type, but it will also not need to be used often, so in this sense it is also suitable. This way, stars, slashes and other markup characters, when found in the original text, can be easily escaped to be rendered as themselves. " So if you need to enter ~ in some text you'll need to enter ~~ For URLs here's what wikimodel recognizes right now: // = ======================================================================== // URI syntax recognition. // = ======================================================================== // This grammar recognize the full URI syntax with following exceptions: // * It has a simplified hier-part definition: it does not contain an empty // path (so the sequences like "here: " are not recognized as URIs). // * It has a simplified version of the host definition: it does not contain // explicit IP definitions. // * It parses "extended" URI syntax where "opaque" URIs are treated as // having multiple schema parts // Example: in an opaque URI like "download:http://www.foo.com/bar.zip " // the part "download:http" is treated as a "composite" scheme part. // // See also: // * http://tools.ietf.org/html/rfc3986#page-49 - the official URI grammar // * http://en.wikipedia.org/wiki/Uniform_Resource_Identifier // * http://en.wikipedia.org/wiki/URI_scheme#Generic_syntax // * http://www.iana.org/assignments/uri-schemes.html // = ======================================================================== | <#URI: <URI_SCHEME_COMPOSITE> ":" <URI_HIER_PART> ("?" <URI_QUERY>)? ("#" <URI_FRAGMENT>)? > | <#ALPHA: ( ["A"-"Z", "a"-"z"] )> | <#DIGIT: ["0"-"9"]> | <#HEXDIG: ( <DIGIT> | ["A"-"F"] | ["a"-"f"] ) > | <#URI_GEN_DELIMS: [ ":", "/", "?", "#", "[", "]", "@" ]> // Some default can not be accepted in the text - like "," symbols //<#URI_SUB_DELIMS: [ "!", "$", "&", "'", "(", ")", "*", "+", ",", ";", "=" ]> | <#URI_SUB_DELIMS: [ "!", "$", "&", "'", "(", ")", "*", "+", / *",",*/ ";", "=" ]> | <#URI_UNRESERVED: ( <ALPHA> | <DIGIT> | "-" | "." | "_" | "~" )> | <#URI_RESERVED: ( <URI_GEN_DELIMS> | <URI_SUB_DELIMS> ) > | <#URI_SCHEME: <ALPHA> ( <ALPHA> | <DIGIT> | "+" | "-" | "." )* > | <#URI_SCHEME_COMPOSITE: <URI_SCHEME> ( ":" <URI_SCHEME> )* > | <#URI_PCT_ENCODED: "%" <HEXDIG> <HEXDIG> > | <#URI_PCHAR_FIRST: ( <URI_UNRESERVED> | <URI_PCT_ENCODED> | <URI_SUB_DELIMS> ) > | <#URI_PCHAR: ( <URI_PCHAR_FIRST> | ":" | "@" ) > | <#URI_QUERY: ( <URI_PCHAR> | "/" | "?" )* > | <#URI_FRAGMENT: ( <URI_PCHAR> | "/" | "?" )* > // A simplified hier-part definition: it does not contain an empty path. | <#URI_HIER_PART: ( "//" <URI_AUTHORITY> <URI_PATH_ABEMPTY> | <URI_PATH_ABSOLUTE> | <URI_PATH_ROOTLESS> )> | <#URI_AUTHORITY: ( <URI_USERINFO> "@" )? <URI_HOST> ( ":" <URI_PORT> )? > | <#URI_USERINFO: ( <URI_UNRESERVED> | <URI_PCT_ENCODED> | <URI_SUB_DELIMS> | ":" )* > | <#URI_PATH_ABEMPTY: ( "/" <URI_SEGMENT> )* > | <#URI_PATH_ABSOLUTE: "/" ( <URI_SEGMENT_NZ> ( "/" <URI_SEGMENT> )* )? > | <#URI_PATH_ROOTLESS: <URI_PCHAR_FIRST> <URI_SEGMENT_NZ_NC> ( "/" <URI_SEGMENT> )* > | <#URI_SEGMENT: (<URI_PCHAR>)* > | <#URI_SEGMENT_NZ: (<URI_PCHAR>)+ > | <#URI_SEGMENT_NZ_NC: (<URI_UNRESERVED> | <URI_PCT_ENCODED> | <URI_SUB_DELIMS> | "@")+ > | <#URI_PORT: (<DIGIT>)+ > // A simplified version of the host: it does not contain explicit IP definitions | <#URI_HOST: ( <URI_REG_NAME> ) > | <#URI_REG_NAME: ( <URI_UNRESERVED> | <URI_PCT_ENCODED> | <URI_SUB_DELIMS> )* > // = ======================================================================== In any case since we've decided to be as compatible as possible to Creole I think it makes sense. Thanks -Vincent

On Sep 19, 2008, at 2:33 PM, Sergiu Dumitriu wrote: See http://www.wikicreole.org/wiki/Creole1.0 and http://www.wikicreole.org/wiki/Creole1.0#section-Creole1.0-EscapeCharacter Creole has done the work for us. I don't see why we should do it again especially since we want to be compatible with it... Thanks -Vincent

On Sep 19, 2008, at 2:57 PM, Sergiu Dumitriu wrote: Sure. Two more reasons: * we were using ~~ previously for italics and we didn't get any complaint about the fact that ~ were hard to type * I'm pretty sure ~ is less common than \ -Vincent