Fancy index formatting not allowed?

[Mark Christiaens]

I've tried to make my index look good by adding raw index entries.  These
raw index entries should simly be the letters A,B, ..., Z with a colored
box around them.  If I do this Lout produces a

"fatal error: this @Key is not a sequence of one or more words"

error (after a second run).  I don't get it since I make my keys simply
the letters a through z.  What am I doing wrong?  Am I not allowed to add
some formatting to the entries in the index (of course not the index
keys).

Here's a small example which reproduces the problem:

@SysInclude { book }

def @MyIndexSeparator
        named key  {}
        named text {}
{
{ key } @RawIndex { @Box linewidth { none } paint { black } { @B { white
@Color { -text- } } } }
}

@Book
        @Title { Nice Title }

@Preface @Begin
@LP

@MyIndexSeparator key { a } text { A }
@MyIndexSeparator key { b } text { B }
@MyIndexSeparator key { c } text { C }
@MyIndexSeparator key { d } text { D }
@MyIndexSeparator key { e } text { E }
@MyIndexSeparator key { f } text { F }
@MyIndexSeparator key { g } text { G }
@MyIndexSeparator key { h } text { H }
@MyIndexSeparator key { i } text { I }
@MyIndexSeparator key { j } text { J }
@MyIndexSeparator key { k } text { K }
@MyIndexSeparator key { l } text { L }
@MyIndexSeparator key { m } text { M }
@MyIndexSeparator key { n } text { N }
@MyIndexSeparator key { o } text { O }
@MyIndexSeparator key { p } text { P }
@MyIndexSeparator key { q } text { Q }
@MyIndexSeparator key { r } text { R }
@MyIndexSeparator key { s } text { S }
@MyIndexSeparator key { t } text { T }
@MyIndexSeparator key { u } text { U }
@MyIndexSeparator key { v } text { V }
@MyIndexSeparator key { w } text { W }
@MyIndexSeparator key { x } text { X }
@MyIndexSeparator key { y } text { Y }
@MyIndexSeparator key { z } text { Z }

@End @Preface

@Introduction @Begin

@LP Great Introduction

@End @Introduction


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