10.6.1 @syncodeindex: Combining Indices Using @code

When you want to combine functions and concepts into one index, you should index the functions with @findex and index the concepts with @cindex, and use the @syncodeindex command to redirect the function index entries into the concept index.

The @syncodeindex command takes two arguments; they are the name of the index to redirect, and the name of the index to redirect it to. The template looks like this:

@syncodeindex from to

For this purpose, the indices are given two-letter names:

‘cp’

Concept index

‘fn’

Function index

‘ky’

Key index

‘pg’

Program index

‘tp’

Data type index

‘vr’

Variable index

Write a @syncodeindex command before or shortly after the end-of-header line at the beginning of a Texinfo file. For example, to merge a function index with a concept index, write the following:

@syncodeindex fn cp

This causes all entries designated for the function index to merge in with the concept index instead.

To merge both a variable index and a function index into a concept index, write the following:

@syncodeindex vr cp
@syncodeindex fn cp

The @syncodeindex command puts all the entries from the ‘from’ index (the redirected index) into the @code font, overriding whatever default font is used by the index to which the entries are now directed. This way, if you direct function names from a function index into a concept index, all the function names are printed in the @code font as you would expect.