Lib shared by markdown and filters for manipulating attributes in an internally-used vocabulary for tunneling markdown meta attributes to later stages via standard SAX events.
The vocabulary for doing this contain the attributes markdown:roundtrip
and markdown:prunable) and is used to
- tunnel fallback content for forward-referenced links which never get declared later (ie. tunnel original input character data received by markdown to Tokenizer such that on unresolved entities, when roundtrip content is present, that content will be output)
- prevent filtering
<p>tags from list items which only consist of a single paragraph when the paragraph markup came from verbatim input HTML (whereas markdown-generated single<p>s get collapsed into their containers)
Implementation quirks:
- in the latter case both
markdown:prunableandmarkdown:roundtripare used (markdown:rountripis misused/set to"true"even though the string"true"isn't from input: in markdown.awkjs, a generated element (= not from verbatim tags in input) is always marked withmarkdown:roundtrip="true"`; see note below about a failed attempt to refactor this markdown:roundtripcan be set to any string (such as"false") which doesn't change behaviour; code only checks for existance of themarkdown:rountripattribute- note this was once considered a start for full markdown/HTML roundtripping (ie. have generated HTML contain attributes which can be used to recover exact input markdown) but this never came to be, hence the naming.
Member Details
- add_markdown_roundtrip_content(buffer, attr_content): string static
-
Appends (blindly) supplied string as value of the
markdown:roundtripattribute to a buffer. Note this doesn't check or replace preexisting attribute specifications in the buffer.Parameters
Name Type Description buffer string string to append attribute specification to
attr_content string attribute value to append; note this must be attribute-encoded for syntactically valid serialization into a double-quoted attribute specification
Returns
stringbufferwithmarkdown:roundtrip="<value of attr_content>"appended, with leading blank ifbufferisn't empty
- get_roundtrip_content(attrs): string static
-
Returns, from the supplied attribute specification string, the value of the
markdown:roundtripattribute used by markdown.awkjs to store source markdown text content on markdown-generated HTML elements. Currently, markdown.awkjs makes use of this only on anchors generated from forward links, and for controlling internal empty elements pruning.Parameters
Name Type Description attrs string Returns
string
- has_non_markdown_attributes(attrs): string static
-
Returns (whether the supplied string has) attributes other than those prefixed by
markdown:.Parameters
Name Type Description attrs string Returns
string
- is_prunable(attrs, attrs_array): string static
-
Returns (as empty/non-empty string encoding of a boolean value) whether the supplied attribute string contains only attributes in the markdown vocabulary (indicating that an element is ok to prune since it doesn't origin from inline/block HTML nor has prunable="false").
Used for pruning empty paragraphs and handle "forced" paragraphs in list items (ie. separated with blank lines from preceding list items).
Parameters
Name Type Description attrs string input attributes as string serialization
attrs_array Object.<string, string>= map of input attributes
Returns
string
- set_nonprunable(attrs): string static
-
Returns an attribute string serialization which has all input attributes (of the input serialization), plus
prunable="false"by string concatenation.Parameters
Name Type Description attrs string Returns
string
- strip_markdown_vocabulary(attrs, attrs_array): string static
-
Returns the input string (an HTML/XML attribute string) stripped from markdown-internal attributes, if it has any. This will return the input string unchanged if it hasn't markdown vocab, so can be used to roundtrip inline/block HTML/XML content verbatim; but if it has markdown vocab, it will synthesize a new attribute string. In the latter case the order, character positions and quotedness of attribute specifications aren't preserved.
Parameters
Name Type Description attrs null | string string containing attribute specification(s) ie. a string serialization of attrs_array
attrs_array Object.<string, string> hashmap mapping attribute names to values
Returns
stringattribute serialization of all attributes of
attrs/attrs_array, without those belonging to the markdown vocabulary