Some rough notes on an alternative error recovery strategy in the HTML
parser for validators that is streamable and non-fatal and hopefully
enables more useful error messages.
Needs more tweaking around frameset if checking frameset documents is
desired.
http://www.whatwg.org/specs/web-apps/current-work/multipage/tree-construction.html#parsing-main-inhead
An end tag whose tag name is "head"
- Pop the current node (which will be the head element) off the stack of
open elements.
Anything else
- Pop the current node (which will be the head element) off the stack of
- open elements.
http://www.whatwg.org/specs/web-apps/current-work/multipage/tree-construction.html#the-after-head-insertion-mode
A character token that is one of U+0009 CHARACTER TABULATION, U+000A
LINE FEED (LF), U+000C FORM FEED (FF), U+000D CARRIAGE RETURN (CR),
or U+0020 SPACE
- Insert the character.
+ Ignore the token.
A comment token
- Insert a comment.
+ Ignore the token.
A start tag whose tag name is "html"
- Process the token using the rules for the "in body" insertion mode.
+ Ignore the token.
A start tag whose tag name is "body"
+ Pop the current node (which will be the head element) off the stack of
+ open elements.
A start tag whose tag name is "frameset"
+ Pop the current node (which will be the head element) off the stack of
+ open elements.
A start tag whose tag name is one of: "base", "basefont", "bgsound",
"link", "meta", "noframes", "script", "style", "template", "title"
Parse error.
- Push the node pointed to by the head element pointer onto the stack of
- open elements.
Process the token using the rules for the "in head" insertion mode.
- Remove the node pointed to by the head element pointer from the stack
- of open elements. (It might not be the current node at this point.)
Anything else
+ Pop the current node (which will be the head element) off the stack of
+ open elements.
http://www.whatwg.org/specs/web-apps/current-work/multipage/parsing.html#reconstruct-the-active-formatting-elements
- 1. If there are no entries in the list of active formatting elements,
- then there is nothing to reconstruct; stop this algorithm.
+ 1. Stop this algorithm.
(This isn't necessary for streaming, but is nice for not flooding errors
about a typoed formatting end tag.)
http://www.whatwg.org/specs/web-apps/current-work/multipage/tree-construction.html#parsing-main-inbody
A start tag whose tag name is "html"
Parse error.
- If there is a template element on the stack of open elements, then
- ignore the token.
- Otherwise, for each attribute on the token, check to see if the
- attribute is already present on the top element of the stack of open
- elements. If it is not, add the attribute and its corresponding value
- to that element.
+ Ignore the token.
A start tag whose tag name is "body"
Parse error.
If the second element on the stack of open elements is not a body
element, if the stack of open elements has only one node on it, or if
there is a template element on the stack of open elements, then ignore
the token. (fragment case)
- Otherwise, set the frameset-ok flag to "not ok"; then, for each
- attribute on the token, check to see if the attribute is already
- present on the body element (the second element) on the stack of open
- elements, and if it is not, add the attribute and its corresponding
- value to that element.
+ Ignore the token.
A start tag whose tag name is "frameset"
Parse error.
- If the stack of open elements has only one node on it, or if the
- second element on the stack of open elements is not a body element,
- then ignore the token. (fragment case)
- If the frameset-ok flag is set to "not ok", ignore the token.
- Otherwise, run the following steps:
- Remove the second element on the stack of open elements from its
- parent node, if it has one.
- Pop all the nodes from the bottom of the stack of open elements, from
- the current node up to, but not including, the root html element.
- Insert an HTML element for the token.
- Switch the insertion mode to "in frameset".
+ Ignore the token.
http://www.whatwg.org/specs/web-apps/current-work/multipage/tree-construction.html#adoption-agency-algorithm
- 2. Let outer loop counter be zero.
+ 2. Stop this algorithm.
http://www.whatwg.org/specs/web-apps/current-work/multipage/tree-construction.html#foster-parent
- 7. Let adjusted insertion location be inside previous element, after
- its last child (if any).
+ 7. Let adjusted insertion location be inside target, after its last
+ child (if any).
http://www.whatwg.org/specs/web-apps/current-work/multipage/tree-construction.html#parsing-main-afterbody
A character token that is one of U+0009 CHARACTER TABULATION, U+000A
LINE FEED (LF), U+000C FORM FEED (FF), U+000D CARRIAGE RETURN (CR), or
U+0020 SPACE
- Process the token using the rules for the "in body" insertion mode.
+ Ignore the token.
A comment token
- Insert a comment as the last child of the first element in the stack
- of open elements (the html element).
+ Ignore the token.
http://www.whatwg.org/specs/web-apps/current-work/multipage/tree-construction.html#the-after-after-body-insertion-mode
A comment token
- Insert a comment as the last child of the Document object.
+ Ignore the token.
A DOCTYPE token
- A character token that is one of U+0009 CHARACTER TABULATION, U+000A
- LINE FEED (LF), U+000C FORM FEED (FF), U+000D CARRIAGE RETURN (CR),
- or U+0020 SPACE
A start tag whose tag name is "html"
Process the token using the rules for the "in body" insertion mode.
+ A character token that is one of U+0009 CHARACTER TABULATION, U+000A
+ LINE FEED (LF), U+000C FORM FEED (FF), U+000D CARRIAGE RETURN (CR),
+ or U+0020 SPACE
+ Ignore the token.
--
Simon Pieters
Opera Software
