[OS X TeX] "\mathit allowed only in math mode" error while writing .idx

[Murray Eisenberg]

I’m looking for any possible clues in trying to track down the error with pdflatex

  \mathit allowed only in math mode

encountered while latexmk is writing .idx.

This is occurring, in the first instance with .ind entry

	\item \idxmark{Urysohn Metrization Theorem}, \hyperpage{506}, 
		\mainref{580}

The function \mainref is defined as:

	\newcommand{\mainref}[1]{\textbf{\emph{\hyperpage{#1}}}}

But the error occurs even if I change \mainref to: \newcommand{\mainref}[1]{#1}

The document’s .ist file includes

	item_0  "\n\\item \\idxmark{"
   	delim_0 "}, "

where \idxmark is defined in my preamble by:

	\providecommand\gobbleone[1]{}
	\newcommand{\idxmark}[1]{{\let\gobbleone\relax\markboth{\sffamily\bfseries#1}{\sffamily\bfseries#1}}#1}

If I comment out the \index entries for that “Urysohn Metrization Theorem”, then the same error occurs for other entries.

I APOLOGIZE for not providing a complete, minimal working example for reproducing the error, but I think some clue might help me devise such. The document in question is of book length, with a complex source structure that includes several style files constituting the preamble.

NOTE: This error did not occur a week or two ago, despite no change to my preamble. So I think something has changed in some latex package to cause this.

---
Murray Eisenberg			murrayeisenberg at gmail.com
503 King Farm Blvd #101	Home (240)-246-7240
Rockville, MD 20850-6667	Mobile (413)-427-5334


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