Hyperlink text using variables names do not resolve

[DaveJarvis]

Description Hyperlinks using []() syntax do not resolve when variables are used for the text description.

Replicate Exact and complete steps to reproduce the problem 100% of the time:

1. Create a new .Rmd text file (R Markdown).
2. Create a new definition list.
3. Add a new definition to the list (e.g., name).
4. Set the definition value to an arbitrary value (e.g., Feynman).
5. Return to the text file.
6. Insert a hyperlink using the variable (e.g., [`r#x(v$name)`](http://physics.com)).

Expected The variable is first resolved then the hyperlink is added using the variable's value for the text.

Actual Document parsing error.

Technical This is due to the spell checker parsing the document without using a suitable set of extensions.