Guide to LaTeX (4th Edition) (Tools and Techniques

380 Appendix A. The New Font Selection Scheme (NFSS)
symbols on their own (Section G.4.3). Thus \’{e} in OT1 prints an acute accent
(character 19) over the letter e, while in T1, it prints the single character in
position 233. This behavior is achieved with
\DeclareTextAccent{\’}{OT1}{19}
\DeclareTextComposite{\’}{T1}{e}{233}
The command must already have been defined for the encoding, either with
\DeclareTextAccent or with \DeclareTextCommand; in the latter case, it must
be defined to take a single argument.
All of the above definition commands create new commands for a specific
encoding. If the defined commands are invoked in some other encoding, an
error message is issued. Default definitions may be provided for all unspecified
encodings with
\DeclareTextCommandDefault{\cmd}[narg][opt]{def }
\ProvideTextCommandDefault{\cmd}[narg][opt]{def }
\DeclareTextAccentDefault{\cmd}{code}
\DeclareTextSymbolDefault{\cmd}{code}
where the first two create a default definition that applies to all unspecified
encodings, while the second two declare which encoding is to be taken as the
default.