Delimiters in link and image title attributes

[wooorm]

Note: I posted this on jgm/CommonMark#308 too, in the hope that one of these two projects would update their title rendering to have at least one method in common.

Hey all, I’m currently in the process creating a markdown parser/stringifier (no, not another one, rather, one that focusses on Markdown itself, not HTML :wink:).

During the process of adding CommonMark support, I came across the fact that it is not possible to generate a title attribute, which contains it’s delimiter, which works in Markdown.pl, RedCarpet/GitHub, and CommonMark.

For example:

• [Hello](./world.html "and "matching delimiters"") works in Markdown.pl and on RedCarpet/GitHub, but not in CommonMark;
• [Hello](./world.html "and \"escapes\"") works in CommonMark, but not in Markdown.pl or on RedCarpet/GitHub;
• [Hello](./world.html "and "named entities"") works in CommonMark and Markdown.pl, but not on RedCarpet/GitHub.

(The same goes for images.)

I would like entity support to be added to RedCarpet, as that seems to be the most simple addition.

Is there any interest in adding this support?

---

Support table:

Implementation	Characters	Nested	Mismatched	Escaped	Named Entities	Numbered Entities
Markdown.pl	"	Yes	Yes	No	Yes	Yes
RedCarpet	"	Yes	Yes	No	No	No
CommonMark	"	No	No	Yes	Yes	Yes
Markdown.pl	'	Yes	Yes	No	Yes	Yes
RedCarpet	'	Yes	Yes	No	No	No
CommonMark	'	No	No	Yes	Yes	Yes
Markdown.pl	()	-	-	-	-	-
RedCarpet	()	-	-	-	-	-
CommonMark	()	No	Yes	Yes	Yes	Yes

Fixtures

# Links

## Double quotes

[Hello](./world.html "and text")

[Hello](./world.html "and "matching delimiters"")

[Hello](./world.html "and "mismatched delimiters")

[Hello](./world.html "and \"escapes\"")

[Hello](./world.html "and "named entities"")

[Hello](./world.html "and "numbered entities"")

## Single quotes

[Hello](./world.html 'and text')

[Hello](./world.html 'and 'matching delimiters'')

[Hello](./world.html 'and 'mismatched delimiters')

[Hello](./world.html 'and \'escapes\'')

[Hello](./world.html 'and 'named entities'')

[Hello](./world.html 'and 'numbered entities'')

## Parentheses

[Hello](./world.html (and text))

[Hello](./world.html (and (matching delimiters)))

[Hello](./world.html (and (mismatched delimiters))

[Hello](./world.html (and \(escapes\)))

[Hello](./world.html (and (named entities)))

[Hello](./world.html (and (numbered entities)))

# Images

## Double quotes

![Hello](./world.png "and text")

![Hello](./world.png "and "matching delimiters"")

![Hello](./world.png "and "mismatched delimiters")

![Hello](./world.png "and \"escapes\"")

![Hello](./world.png "and "named entities"")

![Hello](./world.png "and "numbered entities"")

## Single quotes

![Hello](./world.png 'and text')

![Hello](./world.png 'and 'matching delimiters'')

![Hello](./world.png 'and 'mismatched delimiters')

![Hello](./world.png 'and \'escapes\'')

![Hello](./world.png 'and 'named entities'')

![Hello](./world.png 'and 'numbered entities'')

## Parentheses

![Hello](./world.png (and text))

![Hello](./world.png (and (matching delimiters)))

![Hello](./world.png (and (mismatched delimiters))

![Hello](./world.png (and \(escapes\)))

![Hello](./world.png (and (named entities)))

![Hello](./world.png (and (numbered entities)))

[victor-homyakov]

What do dashes in support table mean? I see that nested parentheses are supported by GitHub (RedCarpet), e.g. [example](http://example.com?q=(())): example

[wooorm]

Common mark supports parentheses as delimiters for a title-attribute (see the last section of the examples). RedCarpet/GitHub/Markdown.pl do not. I’m not talking about parentheses in the URL, rather, in or surrounding the title. Sorry for the confusion.