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diff --git a/infrastructure/ace/README b/infrastructure/ace/README deleted file mode 100644 index 275684f..0000000 --- a/infrastructure/ace/README +++ /dev/null @@ -1,69 +0,0 @@ -===== -ACE2 (originally AppJet Code Editor) -===== - -(This doc started Dec 2009 by dgreenspan.) - -ACE2 is EtherPad's editor, a content-editable-based rich text editor -that supports IE6+, FF(2?/)3+, Safari(3?/)4+. It supports -collaborative editing using operation transforms (easysync2), -undo/redo, copy/paste. - -The name "ACE2" is because this is a rewrite of aiba's original -content-editable AppJet Code Editor. - -== Building it - -In this directory, run `bin/make normal etherpad` (requires scala), -which generates `build/ace2.js` and copies this and other files into -the etherpad source tree. To have the script keep running and -automatically rebuild when source files change, run `bin/make auto -etherpad`. - -The original reason for the build process was that ACE needs to -construct two nested iframes on the client, and to do this without -incurring round-trips to the server, it programmatically loads code -into the outer iframe that loads code into the inner iframe; so the -bulk of ACE's code is compressed into a string literal (twice). Later -on, refactoring meant that the source is also divided into more than a -dozen files that the build script combines, and some are also -server-side EtherPad modules or client-side libraries (or both). - -The master copy of the operational transform (OT) library, easysync2, -lives here. - -In the early days it was possible to run ACE in a sort of development -mode, without the compression and iframe injection, by running it out -of the 'www' directory, but this is no longer possible. - -== Browser support - -We went out of our way to support IE6+. IE's design-mode is quite -robust, though there are some differences in manipulation of the -selection and insertion point and in the DOM representation we had to -use. - -We don't support Opera. Opera is a problematic case, because -apparently JS running in different iframes is run concurrently, not -linearized into a single event thread. This seems to be a rather -obscure fact and is almost difficult to believe. As if iframes don't -complicate scripting enough! - -== Syntax highlighting - -Though syntax highlighting predated rich text as the original -motivation for the design of ACE, support was eventually dropped in -EtherPad. At first the plan was to generalize it to other programming -languages, but the task was deprioritized (and difficult), and during -subsequent optimization and refactoring of ACE, calls to the -incremental lexer were stripped out because they complicated things. - -One plan for multi-language syntax highlighting, never implemented, -was to calculate syntax highlighting on the server as a sort of "style -overlay" and feed updates to the client along with updates to the -document text. - -== Changeset format - -See easysync-notes.txt for some notes on the changeset format, which -was redesigned with the advent of rich text. |