Use this module if you need to edit math + markdown and require optimizations for speed and a smooth editing experience.
The
function parse yields a syntax tree (AST: abstract syntax tree). The functions renderHtml,
renderHtmlWithTOC, and renderHtmlWithExternaTOC render the
AST in various forms, as described below.
The idea of the optimizations used in app-demo-optimized
(see the repo)
is to parse the document text when the
document is first opened. The resulting parse
tree is stored as
model.lastAst. Each block in the AST carries
a label (version, id): (Int, Int), where
the id is unique to each block.
Each time the text changes, a new AST is computed
with an incremented version number. The
function Diff.mergeWith equals is applied to
the old and new ASTs
to compute an updated AST. The updated AST
is identical to the new AST except for the id's.
The id of a node in the updated AST is
the same as in the old AST if and only if the type, level,
and content of the node has not changed.
This information is used to signal MathJax not
to re-render mathematical text that is unchanged.
To see where these optimizations are applied,
look for the places in app-demo-optimized/Main.elm
where functions in the modules
ParseWithId and Markdown.ElmWithId are called.
Render a parse tree to Html.
Like renderHtml, but constructs a table of contents.
Like renderHtmlWithTOC, but transforms a parser three into a record,
with fields for the document title, the table of contents, and the body
of the document.
Search the AST for nodes whose label contains the given string, returning the Id of the first node found, if any.
Count the number of display math element blocks in the parse tree
Given a version number, an option defining a flavor of Markdown, and a text string, return a parse tree.