Mdthbs

I am encountering some weird behavior and errors when manipulating strings inside of lettrine arguments: the code either doesn't compile or produces unexpected results. On top of that, it is font-related, e.g., some things work with regular fonts, but fail with some other fonts, such as most of fonts here: https://tug.org/FontCatalogue/otherfonts.html#initials

Any insight into this issue and advice on how one could fix this would be highly appreciated!

Here is a typical example:

documentclass{article}



usepackage{times,lettrine,Eileen,coolstr,stringstrings,xstring}



%renewcommand*{LettrineFontHook}{Eileenfamily}   %%% Eileen fancy drop letter WTF?



newcommand*{first}[1]{substring{#1}{1}{1}}       %%% stringstrings version

%newcommand*{first}[1]{substr{#1}{1}{1}}         %%% coolstr version DOES NOT WORK AT ALL

%newcommand*{first}[1]{StrLeft{#1}{1}}           %%% xstring version DOES NOT WORK AT ALL



begin{document}





lettrine{first{Whaaat}}{hat} the duck?            %%% DOES NOT WORK AS INTENDED WITH EILEEN



vspace{3em}



lettrine{first{What}}{hat} the duck?              %%% DOES NOT WORK AT ALL WITH EILEEN



end{document}

I recommend, in a case like this, doing it with raw TeX, without parsing packages.

documentclass{article}

usepackage{times,lettrine,Eileen}

deffirstaux#1#2relax{{#1}{#2}}

newcommandflettrine[1]{expandafterlettrinefirstaux#1relax}

begin{document}

flettrine{What} the duck?bigskip



renewcommand*{LettrineFontHook}{Eileenfamily}

flettrine{What} the duck?

end{document}

If you wanted to use stringstrings for other reasons (more complex manipulations, for example), I would use substring to store the result in thestring, and then pass thestring on to lettrine, in this fashion:

documentclass{article}

usepackage{times,lettrine,Eileen,coolstr,stringstrings,xstring}

newcommand*{first}[1]{substring[q]{#1}{1}{1}}       %%% stringstrings version

newcommandflettrine[2]{first{#1}lettrine{thestring}{#2}}

begin{document}

flettrine{Whaaat}{hat} the duck?            %%% DOES NOT WORK AS INTENDED WITH EILEEN



vspace{3em}

renewcommand*{LettrineFontHook}{Eileenfamily}   %%% Eileen fancy drop letter WTF?



flettrine{What}{hat} the duck?              %%% DOES NOT WORK AT ALL WITH EILEEN

end{document}

With expl3 it's really easy:

documentclass{article}



usepackage{newtxtext,lettrine,Eileen,xparse}



renewcommand*{LettrineFontHook}{Eileenfamily}   %%% Eileen fancy drop letter WTF?



ExplSyntaxOn

NewDocumentCommand{IiroLettrine}{O{}m}

 {

  lettrine[#1]{tl_range:nnn { #2 } { 1 } { 1 }}{tl_range:nnn { #2 } { 2 } { -1 } }

 }

ExplSyntaxOff



begin{document}



IiroLettrine{What} the duck?



end{document}

The problem with your code is that StrLeft{#1}{1} doesn't produce the first letter, but the set of instructions for printing it, but lettrine wants just a letter (after expansion).

The tl_range:nnn function is fully expandable, so it makes no problem to lettrine. With tl_range:nnn { #1 } { 1 } { 1 } the first item in the argument is delivered; with tl_range:nnn { #1 } { 2 } { -1 } the remaining items are produced (the negative second number means “up to the last item”).

Since small caps are needed, it's better to use newtxtext that provides real small caps, instead of the faked ones you get with times.

You can do it also with xstring, using its trailing optional argument feature:

documentclass{article}



usepackage{newtxtext,lettrine,Eileen,xstring}



renewcommand*{LettrineFontHook}{Eileenfamily}   %%% Eileen fancy drop letter WTF?



newcommand{IiroLettrine}[2][]{%

  StrLeft{#2}{1}[firstletter]%

  StrGobbleLeft{#2}{1}[otherletters]%

  lettrine[#1]{firstletter}{otherletters}%

 }



begin{document}



IiroLettrine{What} the duck?



end{document}

In both cases I kept the optional argument to lettrine available in IiroLettrine.