I love InDesign, even though it sometimes infuriates me. Its built-in indexing is excellent, except that there is no proper way to style parts of an entry. For instance, to italicise book titles.
There are two work-arounds. One is to do a GREP search-and-replace once the index is generated. For instance, one can delimit the italic words with double quotes, than search for text surrounded by double quotes, italicise it and then delete the quotes. The other is to create a GREP style. The former works well (at least if your grasp of GREP patterns is at lot better than mine) but you have to perform these after every regeneration of the index (and, in my experience, that's quite often).
The idea of GREP styles is very clever. You define a character style, say italic, which inherits all the characteristics of the paragraph to which it belongs except that it is italic. You then go to the relevant paragraph styles, such as level 1, level 2 and level 3 index entries and define in the GREP styles tab the circumstances in which the character style is applied.
The picture shows a simple pattern searching for any text contained within any type of double quotes and then applying an italic character style. However, that doesn't get rid of the double quotes so you then have to apply a style to them, in this case a style which makes them very narrow and of no colour.
In other words, the GREP style doesn't get rid of the double quotes at all, it just hides them. This is unsatisfactory for two reasons. First, imagine you, like I, want to include headwords in the running head. This is easy with InDesign's text variables. You can set up a text variable to display the first word of the first level 1 heading on the page and another to display the first word of the last level 1 heading on the page. Great! But if you marked your italics with double quotes they're still there. Moreover, InDesign doesn't allow you to do GREP searches on text variable, so you can't hide those double quotes again, so there they are in the running head.
The second, possibly more serious, problem with this scenario is that you'll probably want to create other forms of this publication, such as Kindle and ePub. All those double quotes will reappear again!
There is only one sensible solution to this, I think: Adobe should support some sort of tagging in the index.
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