diagrams.sty can't draw \ruTo(4,2)

Question

I ran into a problem of drawing an arrow \ruTo(4,2). The following example didn't draw the diagonal arrow, as in

However, it works well for \rdTo(4,2) and \ruTo(2,2), as in

and

I'm really confused and would appreciate it if someone could help me solve this problem. Thank you.

\documentclass[a4paper,11pt]{article}
\usepackage[small,nohug,heads=LaTeX]{diagrams}
\diagramstyle[labelstyle=\scriptstyle]

\begin{document}
\begin{diagram}
    a&\rTo&a&\rTo&a\\
    \dTo&\ruTo(4,2)&&&\dTo\\
    a&\rTo&a&\rTo&a
\end{diagram}
\end{document}

I think I found a solution to my problem by replacing the second line of the diagram with \dTo&&&\ruTo(4,2)&\dTo\ — Pumpkinification, Nov 27 '18 at 00:00
I’m voting to close this question because teh OP commented "problem solved", long ago. — MS-SPO, Feb 01 '24 at 18:36
Voting to reopen, closing a question as "solved in comments" is not a good idea, see e.g. https://tex.meta.stackexchange.com/a/8778/36296 — samcarter_is_at_topanswers.xyz, Feb 02 '24 at 00:41
@samcarter_is_at_topanswers.xyz -- Please also post a brief answer based on the comment. — barbara beeton, Feb 02 '24 at 02:29
@barbarabeeton Will post a community wiki answer as soon as the question is reopened — samcarter_is_at_topanswers.xyz, Feb 02 '24 at 09:25

samcarter_is_at_topanswers.xyz · Answer 1 · 2024-02-02T13:51:00.760

As commented by the OP, the problem can be solved by using \dTo&&&\ruTo(4,2)&\dTo\\

Full MWE:

\documentclass[a4paper,11pt]{article}
\usepackage[small,nohug,heads=LaTeX]{diagrams}
\makeatletter
\def\foo#1\endgraf\unskip#2\foo{\def\row@to@buffer{#1\endgraf\unskip\unskip#2}}
\expandafter\foo\row@to@buffer\foo
\makeatother
\diagramstyle[labelstyle=\scriptstyle]
\begin{document}
\begin{diagram}
    a&\rTo&a&\rTo&a\
    \dTo&&&\ruTo(4,2)&\dTo\ 
    a&\rTo&a&\rTo&a
\end{diagram}
\end{document}

Some useful hints how to get the diagrams package and compile documents using the package can be found in these answers:

diagrams.sty can't draw \ruTo(4,2)

1 Answers1