There was some proposal on [Talk.Creole0.3] to change the markup for italic text. This page serves to collect the advantages and disadvantages of such an action, and to research valid alternatives for italic markup.

Please feel free to add or correct facts. For discussion, see [Talk.ChangeItalicsMarkupProposal].

!!!Slashes

The current way to mark italics in Creole is to use double slash characters on both sides of the italic text, {{{//like this//}}}.

!!Advantages

* Already in spec (no change required, no need to convert existing pages)
* Used for italics by at least 15 popular wiki engines (NotNew)
* Not used for anything else by any known wiki engine (CollisionFree)
* Visually suggesting slanted text (EasyToLearn)
* Easy to type (FastToType)

!!Disadvantages

* Possible confusion with URLs (but URLs require "://")
* Double slash could be used for forced line break instead

!!!Tilde
The proposition is to use a double tilde character instead of the double slash, {{{~~like this~~ }}}.

!!Advantages

* Used for italics by at least 3 wiki engines
* No confusion with URLs

!!Disadvantages

* Used for different purposes by at least 9 wiki engines (one for monospace, 2 for strike, 6 for subscript)
* Hard to type (on windows machines you need to type tilde, space, tilde, space)
* Not in the range of characters allowed in Creole (see [Terms])
* Not obvious (against EasyToLearn)
* Requires a change in the spec
* Possible collision with the signature mark used by some wikis

!!!Underscore
The proposition is to use a double underscore character instead of the double slash, {{{__like this__}}}.

!!Advantages
* No confusion with URLs
* Used for italics by at least 7 popular wiki engines (NotNew)
* Used for various forms of emphasis by at least 38 wiki engines (7 for italics, 8 for bold, 23 for underline)
* Is tradidtionally used to mark italic text whenever italics are not technically available (UnderlineIsItalics)
* Used for italics in a number of non-wiki text markups, see http://www.c2.com/cgi/wiki?AlmostFreeText (NotNew)
* Easy to type (FastToType)
* Since we don't need underlined or subscript text, the underscores are not immediately useful for any other markup

!!Disadvantages
* Requires a change in the spec
* Is used for underline in 23 engines, this means it would confuse existing users (against EasyToLearn and CollisionFree)
* Visually suggesting underline (against EasyToLearn)
* Possible collision with underline (23 wikis), bold (8 wikis) or subscript (1 wiki)