我在使用 devtools 函数时遇到了非常奇怪的副作用。这是一个简单的例子。 基本上，我启动一个干净的 R session ，创建一个空包，然后使用 load_all 加载新包。一旦我这样做了，帮助功能就不再起作用了。这是屏幕截图:
R version 3.1.0 (2014-04-10) -- "Spring Dance"
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> setwd("c:/Scratch")
> require(devtools)
Loading required package: devtools
Attaching package: ‘devtools’
The following objects are masked from ‘package:utils’:
?, help
The following object is masked from ‘package:base’:
system.file
> help("data.frame")
starting httpd help server ... done
> create("mypackage",rstudio=F)
Creating package mypackage in .
No DESCRIPTION found. Creating with values:
Package: mypackage
Title: What the package does (short line)
Version: 0.1
Authors@R: "First Last <first.last@example.com> [aut, cre]"
Description: What the package does (paragraph)
Depends: R (>= 3.1.0)
License: What license is it under?
LazyData: true
> help("data.frame")
> load_all("mypackage")
Loading mypackage
> help("data.frame")
Error in names(t1) <- rep(names(L), lapply(L, length)) :
attempt to set an attribute on NULL
>
这是 session 信息:
> sessionInfo()
R version 3.1.0 (2014-04-10)
Platform: i386-w64-mingw32/i386 (32-bit)
attached base packages:
[1] stats graphics grDevices utils datasets methods base
other attached packages:
[1] mypackage_0.1 devtools_1.5
loaded via a namespace (and not attached):
[1] digest_0.6.4 evaluate_0.5.5 httr_0.3 memoise_0.2.1 parallel_3.1.0 RCurl_1.95-4.1 stringr_0.6.2 tools_3.1.0 whisker_0.3-2
>
帮助命令不起作用只是一个例子，我注意到还有一些其他奇怪的东西。像 data.table 子集功能不再工作。如果您能给我一些解决问题的建议，我将不胜感激。
最佳答案
这是 devtools 1.5 中的一个错误，当项目没有帮助文件时会发生。我刚刚推送了一个修复程序。
在非 Windows 平台上，您可以使用 devtools::install_github('hadley/devtools') 更新到最新版本。在 Windows 上，请参阅 ?build_github_devtools 以获取有关如何更新的说明。
关于r - 如何解决 devtools 不需要的副作用，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/24036019/