linux - cpan 安装开关失败

Question

我是新手，学习 Perl 编程。我对 cpan 感到困惑，我知道有数千个库支持 perl，但是，如何从 cpan 安装库？我在 linux 中使用 cpan，当我尝试安装 switch 时，出现错误消息

cpan[1]> install Switch

安装时出错:

Reading '/root/.cpan/Metadata'
Database was generated on Mon, 13 Jan 2014 08:29:02 GMT
Running install for module 'Switch'
Running make for R/RG/RGARCIA/Switch-2.16.tar.gz
Checksum for /root/.cpan/sources/authors/id/R/RG/RGARCIA/Switch-2.16.tar.gz ok
Scanning cache /root/.cpan/build for sizes
............................................................................DONE

  CPAN.pm: Building R/RG/RGARCIA/Switch-2.16.tar.gz

Checking if your kit is complete...
Looks good
Writing Makefile for Switch
Writing MYMETA.yml and MYMETA.json
cp Switch.pm blib/lib/Switch.pm
Manifying blib/man3/Switch.3
  RGARCIA/Switch-2.16.tar.gz
  /usr/bin/make -- OK
'YAML' not installed, will not store persistent state
Running make test
PERL_DL_NONLAZY=1 /usr/bin/perl5.18.1 "-MExtUtils::Command::MM" "-e" "test_harness(0, 'blib/lib', 'blib/arch')" t/*.t
t/given.t ... Failed 2/293 subtests 
t/nested.t .. ok   
t/switch.t .. ok       

Test Summary Report
-------------------
t/given.t (Wstat: 0 Tests: 293 Failed: 2)
  Failed tests:  2-3
Files=3, Tests=590,  4 wallclock secs ( 0.31 usr  0.01 sys +  2.38 cusr  0.03 csys =  2.73 CPU)
Result: FAIL
Failed 1/3 test programs. 2/590 subtests failed.
make: *** [test_dynamic] Error 255
  RGARCIA/Switch-2.16.tar.gz
  /usr/bin/make test -- NOT OK
//hint// to see the cpan-testers results for installing this module, try:
  reports RGARCIA/Switch-2.16.tar.gz
Running make install
  make test had returned bad status, won't install without force
Failed during this command:
 RGARCIA/Switch-2.16.tar.gz                   : make_test NO

如何安装开关？ 谢谢

Answer 1

你做的一切都是对的，但是开关是broken on Perl 5.13.3 and above 。模块的维护者知道这个问题，但似乎对修复它不感兴趣。鉴于该模块的维护不善，即使您确实说服它安装，在生产代码中使用它似乎也是不可取的。

最近关于 PerlMonks 的一些相关讨论讨论了类似开关的结构:

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