我正在尝试运行 SWI-Prolog 的 simplex 库文档中给出的硬币示例，但我收到了以下错误消息：
$ rlwrap swipl coins.pl
Warning: /home/vitorferraz/junk/coins.pl:1:
Unknown message: simlpex(bounded)
Welcome to SWI-Prolog (threaded, 64 bits, version 7.6.4)
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1 ?- coins(S), variable_value(S, c(1), C1), variable_value(S, c(5), C5), variable_value(S, c(20), C20).
ERROR: Arithmetic: `rationalize/1' is not a function
ERROR: In:
ERROR: [13] _5574 is rationalize(111)
ERROR: [12] simplex:constraint_(0,[...|...]=111,state(0,[],[],[]),_5616) at /usr/local/lib/swipl-7.6.4/library/clp/simplex.pl:636
ERROR: [10] coins(state(0,[],[],[]),_5664) at /home/vitor/coins.pl:8
ERROR: [8] '<meta-call>'(user:(...,...)) <foreign>
ERROR: [7] <user>
ERROR:
ERROR: Note: some frames are missing due to last-call optimization.
ERROR: Re-run your program in debug mode (:- debug.) to get more detail.