sub classes_from_latex {
my ($path, $class) = @_;
+ eval { use String::ShellQuote; 1 } or warn "can't load String::ShellQuote" && return;
+ $path = shell_quote $path;
+ $class = shell_quote $class;
+
open my $pipe, q#egrep -rs '^[\ \t]*# . "$class' $path". q# | sed 's/ //g' | awk -F '{' '{print $2}' | awk -F '}' '{print $1}' |#;
my @cls = <$pipe>;
close $pipe;