¿Cómo insertar el próximo mes, como /hoy?

Question

Me gustaría crear un comando que insertaría el próximo mes (en relación con el actual), así:

\command-> noviembre

análogamente a \today.

• El comando no se puede codificar, ya que el documento cambia entre idiomas (de la misma manera que funciona con \today).
• Me gustaría usar este comando dentro del preámbulo.
• La salida debe estar localizada, es decir, en otro lugar, \todaydebe comportarse como de costumbre.

¿Cuál es la mejor manera de hacer esto?

Answer 1

Conseguí que algo como esto funcione:

\usepackage{datetime}
\usepackage{advdate}

\newdateformat{mydate}{\monthname[\THEMONTH]}

(...)

{\AdvMonth{1} \mydate \today}

Answer 2

Aquí hay una solución que usa datetime2un poco de aritmética modular.

\documentclass{article}
\usepackage[french,english]{babel}
\usepackage[T1]{fontenc}
\usepackage[calc]{datetime2}
\ExplSyntaxOn
\NewDocumentCommand{\nextmonth} {} {
\int_eval:n {12 - \int_mod:nn {\month}{12}}{=}{0}}
\DTMmonthname{\nxtmnth:n}}
\ExplSyntaxOff
\begin{document}
Today is: \today

Next month is \nextmonth
\selectlanguage{french}

En français: \nextmonth

\end{document}

Answer 3

Para hacer álgebra módulo doce puedes usar expl3's \int_mod:nndonde el valor absoluto del resultado es menor que el valor absoluto del módulo y donde el signo del resultado es el mismo que el de la expresión cuyo resto entero se calculará:

Probablemente proporcionando el resultado del cálculo.

12 - (
         (
             % With \int_mod:nn for doing the mod-12-calculation this
             % expression yields a non-negative number...
             12 - ( 
                      % ... because this is in range -11..+11 :
                      (   ⟨number of current month⟩
                        + ⟨amount of months to add or subtract⟩
                      ) mod 12 
                  )
         ) mod 12  
         % With \int_mod:nn the result of mod-12-calculation of a
         % non-negative number is in range 0..11.
     )

afechahora2Esto \DTMmonthnamefunciona:

\documentclass{article}
\usepackage[french,english]{babel}
\usepackage[T1]{fontenc}
\usepackage[calc]{datetime2}
\ExplSyntaxOn
\NewDocumentCommand{\MonthInRelationToCurrentMonth} {m} {
  \exp_args:Nf \DTMmonthname
               {\int_eval:n {12-\int_mod:nn {12-(\int_mod:nn{\month+(#1)}{12})}{12}}}
}
\ExplSyntaxOff
\newcommand\NextMonth{\MonthInRelationToCurrentMonth{1}}%
\newcommand\PreviousMonth{\MonthInRelationToCurrentMonth{-1}}%
\newcommand\ThisMonth{\MonthInRelationToCurrentMonth{0}}%

\begin{document}
\bigskip\hrule\bigskip
\noindent In English
\bigskip\hrule\bigskip
\noindent 
Today is \today.\\
Previous month was \PreviousMonth.\\
This month is \ThisMonth.\\
Next month will be \NextMonth.

\bigskip\hrule\bigskip

\noindent 
This month is \MonthInRelationToCurrentMonth{0}.\\
This month is  \MonthInRelationToCurrentMonth{+0}.\\
One month later will be \MonthInRelationToCurrentMonth{+1}.\\
Two months later will be \MonthInRelationToCurrentMonth{2}.\\
Three months later will be \MonthInRelationToCurrentMonth{3}.\\
Four months later will be \MonthInRelationToCurrentMonth{4}.\\
Five months later will be \MonthInRelationToCurrentMonth{+5}.\\
Six months later will be \MonthInRelationToCurrentMonth{+6}.\\
Seven months later will be \MonthInRelationToCurrentMonth{7}.\\
Eight months later will be \MonthInRelationToCurrentMonth{8}.\\
Nine months later will be \MonthInRelationToCurrentMonth{9}.\\
Ten months later will be \MonthInRelationToCurrentMonth{10}.\\
Eleven months later will be \MonthInRelationToCurrentMonth{11}.\\
Twelve months later will be \MonthInRelationToCurrentMonth{12}.\\
Thirteen months later will be \MonthInRelationToCurrentMonth{13}.\\
Twenty months later will be \MonthInRelationToCurrentMonth{+20}.

\bigskip\hrule\bigskip

\noindent 
This month is \MonthInRelationToCurrentMonth{0}.\\
This month is  \MonthInRelationToCurrentMonth{-0}.\\
One month earlier was \MonthInRelationToCurrentMonth{-1}.\\
Two months earlier was \MonthInRelationToCurrentMonth{-2}.\\
Three months earlier was \MonthInRelationToCurrentMonth{-3}.\\
Four months earlier was \MonthInRelationToCurrentMonth{-4}.\\
Five months earlier was \MonthInRelationToCurrentMonth{-5}.\\
Six months earlier was \MonthInRelationToCurrentMonth{-6}.\\
Seven months earlier was \MonthInRelationToCurrentMonth{-7}.\\
Eight months earlier was \MonthInRelationToCurrentMonth{-8}.\\
Nine months earlier was \MonthInRelationToCurrentMonth{-9}.\\
Ten months earlier was \MonthInRelationToCurrentMonth{-10}.\\
Eleven months earlier was \MonthInRelationToCurrentMonth{-11}.\\
Twelve months earlier was \MonthInRelationToCurrentMonth{-12}.\\
Thirteen months earlier was \MonthInRelationToCurrentMonth{-13}.\\
Twenty months earlier was \MonthInRelationToCurrentMonth{-20}.

\newpage
\selectlanguage{french}

\bigskip\hrule\bigskip
\noindent En français:
\bigskip\hrule\bigskip
\noindent 
Aujourd'hui, c'est \today.\\
Le mois précédent était \PreviousMonth.\\
Ce mois-ci est \ThisMonth.\\
Le mois prochain sera \NextMonth.

\bigskip\hrule\bigskip

\noindent 
Ce mois-ci, c'est \MonthInRelationToCurrentMonth{0}.\\
Ce mois-ci, c'est \MonthInRelationToCurrentMonth{+0}.\\
Un mois plus tard sera \MonthInRelationToCurrentMonth{+1}.\\
Deux mois plus tard sera \MonthInRelationToCurrentMonth{2}.\\
Trois mois plus tard sera \MonthInRelationToCurrentMonth{3}.\\
Quatre mois plus tard sera \MonthInRelationToCurrentMonth{4}.\\
Cinq mois plus tard sera \MonthInRelationToCurrentMonth{+5}.\\
Six mois plus tard sera \MonthInRelationToCurrentMonth{+6}.\\
Sept mois plus tard sera \MonthInRelationToCurrentMonth{7}.\\
Huit mois plus tard sera \MonthInRelationToCurrentMonth{8}.\\
Neuf mois plus tard sera \MonthInRelationToCurrentMonth{9}.\\
Dix mois plus tard plus tard sera \MonthInRelationToCurrentMonth{10}.\\
Onze mois plus tard plus tard sera \MonthInRelationToCurrentMonth{11}.\\
Douze mois plus tard plus tard sera \MonthInRelationToCurrentMonth{12}.\\
Treize mois plus tard plus tard sera \MonthInRelationToCurrentMonth{13}.\\
Vingte mois plus tard plus tard sera \MonthInRelationToCurrentMonth{+20}.

\bigskip\hrule\bigskip

\noindent 
Ce mois-ci, c'est \MonthInRelationToCurrentMonth{0}.\\
Ce mois-ci, c'est \MonthInRelationToCurrentMonth{+0}.\\
Un mois plus tôt, c'était \MonthInRelationToCurrentMonth{-1}.\\
Deux mois plus tôt, c'était \MonthInRelationToCurrentMonth{-2}.\\
Trois mois plus tôt, c'était \MonthInRelationToCurrentMonth{-3}.\\
Quatre mois plus tôt, c'était \MonthInRelationToCurrentMonth{-4}.\\
Cinq mois plus tôt, c'était \MonthInRelationToCurrentMonth{-5}.\\
Six mois plus tôt, c'était \MonthInRelationToCurrentMonth{-6}.\\
Sept mois plus tôt, c'était \MonthInRelationToCurrentMonth{-7}.\\
Huit mois plus tôt, c'était \MonthInRelationToCurrentMonth{-8}.\\
Neuf mois plus tôt, c'était \MonthInRelationToCurrentMonth{-9}.\\
Dix mois plus tôt, c'était \MonthInRelationToCurrentMonth{-10}.\\
Onze mois plus tôt, c'était \MonthInRelationToCurrentMonth{-11}.\\
Douze mois plus tôt, c'était \MonthInRelationToCurrentMonth{-12}.\\
Teize mois plus tôt, c'était \MonthInRelationToCurrentMonth{-13}.\\
Vingte mois plus tôt, c'était \MonthInRelationToCurrentMonth{-20}.

\end{document}