pstricks 回归？

Question

下面的pstricks代码是我之前发现的，可以用 TeX Live 2013 很好地编译：

\documentclass[pstricks,border=12pt,12pt]{standalone}
\usepackage{pst-plot}
\psset{unit=2cm,dimen=m}
\newdimen\Width\Width=3.64159265\psxunit

\begin{document}
\multido{\i=0+10}{19}{%
\begin{pspicture}(-.5,-.2)(\Width,1)
    \psaxes[yAxis=false](0,0)(-.5,0)(\Width,0)
    \multips(.5,.5)(1,0){3}{\pscircle[linecolor=cyan!20]{.5}}
    \pstVerb{/length {\i\space DegtoRad} def /angle {\i\space .5 div 90 add neg} def}
    \rput(!length .5){\psline{->}(!.5 angle PtoC)}
    \ifnum\i=180\color{red}\psxTick[labelsep=1pt](3.14159265){\pi}\fi
    \psset{linewidth=2pt}
    \pscircle(!length .5){.5}
    \psline[linecolor=red](!length 0)
    \psarcn[linecolor=red](!length .5){.5}{-90}{!angle}
\end{pspicture}}
\end{document}

但是我刚刚更新到 TeX Live 2017，现在我得到：

$ xelatex pi.tex
This is XeTeX, Version 3.14159265-2.6-0.99998 (TeX Live 2017) (preloaded format=xelatex)
 restricted \write18 enabled.
entering extended mode
(./pi.tex
LaTeX2e <2017-04-15>
Babel <3.15> and hyphenation patterns for 84 language(s) loaded.

...

Overfull \hbox (170.7165pt too wide) detected at line 18
[] [] [] []
[1]

重复 15 次，然后

[15]
Overfull \hbox (170.7165pt too wide) detected at line 18
[] [] [] []
[16Error: /typecheck in --moveto--
Operand stack:
   --nostringval--   0.0   -28.4527   0.0   -28.4527   0   0   ()
Execution stack:
   %interp_exit   .runexec2   --nostringval--   --nostringval--   --nostringval--   2   %stopped_push   --nostringval--   --nostringval--   --nostringval--   false   1   %stopped_push   2015   1   3   %oparray_pop   2014   1   3   %oparray_pop   1998   1   3   %oparray_pop   1884   1   3   %oparray_pop   --nostringval--   %errorexec_pop   .runexec2   --nostringval--   --nostringval--   --nostringval--   2   %stopped_push   --nostringval--   --nostringval--   --nostringval--
Dictionary stack:
   --dict:989/1684(ro)(G)--   --dict:1/20(G)--   --dict:166/200(L)--   --dict:126/200(L)--
Current allocation mode is local
Current file position is 2465
GPL Ghostscript 9.22: Unrecoverable error, exit code 1
Error: /typecheck in --moveto--

...

--dict:130/200(L)--
Current allocation mode is local
Current file position is 2321
GPL Ghostscript 9.22: Unrecoverable error, exit code 1
(see the transcript file for additional information)
Output written on pi.pdf (19 pages).
Transcript written on pi.log.
$

有人知道代码是否错误或者pstricks包中（或其他地方）存在回归吗？

Answer 1

以前也是这样。/length无法定义，这是保留的 PostScript 函数名！使用类似名称，例如/Length：

\documentclass[pstricks,border=12pt,12pt]{standalone}
\usepackage{pst-plot}
\psset{unit=2cm,dimen=m}
\newdimen\Width\Width=3.64159265\psxunit

\begin{document}
    \multido{\i=0+10}{19}{%
        \begin{pspicture}(-.5,-.2)(\Width,1)
        \psaxes[yAxis=false](0,0)(-.5,0)(\Width,0)
        \multips(.5,.5)(1,0){3}{\pscircle[linecolor=cyan!20]{.5}}
        \pstVerb{/Length {\i\space DegtoRad} def /angle {\i\space .5 div 90 add neg} def}
        \rput(!Length .5){\psline{->}(!.5 angle PtoC)}
        \ifnum\i=180\color{red}\psxTick[labelsep=1pt](3.14159265){\pi}\fi
        \psset{linewidth=2pt}
        \pscircle(!Length .5){.5}
        \psline[linecolor=red](!Length 0)
        \psarcn[linecolor=red](!Length .5){.5}{-90}{!angle}
        \end{pspicture}}
\end{document}