我正在使用refsegment功能biblatex在同一文档中汇编多个参考书目。我希望在refsegments 中有连续的参考编号（即，如果为 N 的最后一个新参考refsegment分配了编号i，则为 N+1 的第一个新参考refsegment分配了编号i+1）。我还想避免在子参考书目中重复已引用的参考文献。也就是说，虽然给定的参考文献可能在多个 中被引用refsegment，但它应该仅包含在它首次出现的 的子参考书目中refsegment。这是一个简单的例子：
refsegment #1:
The quick brown fox [1] jumps over the lazy dog [2].
Bibliography:
[1] Fox reference.
[2] Dog reference.
refsegment #2:
The lazy dog [2] was busy doing nothing [3].
Bibliography:
[3] Reference on nothing.
请注意，参考文献 #2 虽然在第二个参考书目中被引用，但却没有包含在第二个参考书目中，refsegment因为它已经包含在第一个参考书目中。
这个帖子提出了一种解决该问题的方法，即onlynew书目检查，它可以抑制重复的书目项。提出的解决方案会持续记录书目项（存储在控制序列中\blx@entrycount），并在每个书目项的开头记录下一个参考编号refsegment（在控制序列中\blx@entrycount@\the\c@refsegment）。然后，如果分配给给定书目项的编号（\thefield{labelnumber}）小于（\ifnumless{}）后一个数量，则在书目中跳过它（因为它已经被引用）。但是，在编译时（TeX Live 2019），所有引用都被分配了数字零，书目为空，并发出以下警告：
LaTeX Warning: Empty bibliography on input line <n>
以下示例重现了该问题。需要进行哪些更改才能修复 MWE 中的代码？
平均能量损失（改编自链接文章）：
\documentclass{article}
\usepackage[defernumbers=true]{biblatex}
\usepackage{filecontents}
\makeatletter
% Overall entry counter
\csnumgdef{blx@entrycount}{0}
\AtEveryBibitem{%
\csnumgdef{blx@entrycount}{\csuse{blx@entrycount}+1}}
% Continued from this label number
\appto{\newrefsegment}{%
\csnumgdef{blx@entrycount@\the\c@refsegment}{\csuse{blx@entrycount}+1}}
% Skip entries with label numbers less than the continued number
\defbibcheck{onlynew}{%
\ifnumless{\thefield{labelnumber}}{\csuse{blx@entrycount@\the\c@refsegment}}
{\skipentry}
{}}
\makeatother
\begin{filecontents}{\jobname.bib}
@Book{companion,
author = {Goossens, Michel and Mittelbach, Frank and Samarin, Alexander},
title = {The LaTeX Companion},
edition = {1},
publisher = {Addison-Wesley},
location = {Reading, Mass.},
date = {1994}}
@Article{gillies,
author = {Gillies, Alexander},
title = {Herder and the Preparation of Goethe's Idea of World Literature},
journaltitle = {Publications of the English Goethe Society},
volume = {9},
date = {1933},
pages = {46--67}}
@Article{bertram,
author = {Bertram, Aaron and Wentworth, Richard},
title = {Gromov invariants for holomorphic maps on Riemann surfaces},
journaltitle = {J.~Amer. Math. Soc.},
volume = {9},
number = {2},
date = {1996},
pages = {529--571}}
@Book{poetics,
author = {Aristotle},
editor = {Lucas, D. W.},
title = {Poetics},
series = {Clarendon Aristotle},
publisher = {Clarendon Press},
location = {Oxford},
date = {1968}}
@Book{rhetoric,
author = {Aristotle},
editor = {Cope, Edward Meredith},
commentator = {Cope, Edward Meredith},
title = {The Rhetoric of Aristotle with a commentary by the late Edward Meredith Cope},
volumes = {3},
publisher = {Cambridge University Press},
date = {1877}}
\end{filecontents}
\addbibresource{\jobname.bib}
\begin{document}
\newrefsegment
refsegment \therefsegment:
\cite{companion,rhetoric}
\printbibliography[segment=\therefsegment,check=onlynew]
\newrefsegment
refsegment \therefsegment:
\cite{companion,bertram,poetics}
\printbibliography[segment=\therefsegment,check=onlynew]
\newrefsegment
refsegment \therefsegment:
\cite{companion,bertram,gillies,rhetoric}
\printbibliography[segment=\therefsegment,check=onlynew]
\end{document}
编译：pdflatex && biber && pdflatex && pdflatex
输出：
答案1
引用的答案已有八年多历史，从那时起一些内部事情已经发生了变化。我不能完全确定，但主要问题似乎是选项defernumbers。所有labelnumbers 最初都设置为 0，并且只有在参考书目中打印条目后才会分配非零数字。不幸的是，\ifnumless{\thefield{labelnumber}}{\csuse{blx@entrycount@\the\c@refsegment}}如果 为 0，则测试将始终为真labelnumber，因此每个参考书目中都会跳过所有条目，这意味着参考书目保持为空，因此blx@entrycount永远不会增加。
我建议使用以下希望更稳定的解决方案。对于每个条目，它会记录refsegment它被引用的第一个条目。onlynew然后过滤器只需要检查这个条目refsegment的数字是否小于当前的数字refsegment。
\documentclass{article}
\usepackage[defernumbers=true]{biblatex}
\makeatletter
\AtEveryCitekey{%
\ifcsundef{blx@entry@refsegment@\the\c@refsection @\thefield{entrykey}}
{\csnumgdef{blx@entry@refsegment@\the\c@refsection @\thefield{entrykey}}{\the\c@refsegment}}
{}}
\defbibcheck{onlynew}{%
\ifnumless{0\csuse{blx@entry@refsegment@\the\c@refsection @\thefield{entrykey}}}{\the\c@refsegment}
{\skipentry}
{}}
\makeatother
\addbibresource{biblatex-examples.bib}
\begin{document}
\newrefsegment
refsegment \therefsegment:
\cite{sigfridsson,worman}
\printbibliography[segment=\therefsegment,check=onlynew]
\newrefsegment
refsegment \therefsegment:
\cite{sigfridsson,geer,nussbaum}
\printbibliography[segment=\therefsegment,check=onlynew]
\newrefsegment
refsegment \therefsegment:
\cite{sigfridsson,geer,pines,worman}
\printbibliography[segment=\therefsegment,check=onlynew]
\end{document}
这是一个同样适用于 的解决方案\nocite。该钩子\AtEveryEntrykey是在biblatex3.15 中添加的（请参阅https://github.com/plk/biblatex/issues/934）。如果您使用的是旧版本的biblatex，请参阅编辑历史以找到解决方法。
\documentclass{article}
\usepackage[defernumbers=true]{biblatex}
\makeatletter
\AtEveryEntrykey{%
\ifcsundef{blx@entry@refsegment@\the\c@refsection @#1}
{\csnumgdef{blx@entry@refsegment@\the\c@refsection @#1}{\the\c@refsegment}}
{}}
{}{}
\defbibcheck{onlynew}{%
\ifnumless{0\csuse{blx@entry@refsegment@\the\c@refsection @\thefield{entrykey}}}{\the\c@refsegment}
{\skipentry}
{}}
\makeatother
\addbibresource{biblatex-examples.bib}
\begin{document}
\newrefsegment
refsegment \therefsegment:
\cite{sigfridsson,worman}
\printbibliography[segment=\therefsegment,check=onlynew]
\newrefsegment
refsegment \therefsegment:
\cite{sigfridsson,geer,nussbaum}\nocite{knuth:ct:a}
\printbibliography[segment=\therefsegment,check=onlynew]
\newrefsegment
refsegment \therefsegment:
\cite{sigfridsson,geer,pines,worman}\nocite{knuth:ct:a,knuth:ct:b}
\printbibliography[segment=\therefsegment,check=onlynew]
\end{document}