R 4.0 安装中遇见的问题

1. Rstudio无法定位程序输入点于动态链接库R.dll上
   解决方法是，4.0.2就不会报错了。4.0以上需要安装更高级别的rtools。
2. 无法加载tidyverse，报错：

Error: package or namespace load failed for ‘tidyverse’:
 .onAttach failed in attachNamespace() for 'tidyverse', details:
  call: namespaceExport(ns, exports)
  error: undefined exports: addTheme, applyTheme, as.document_position, as.document_range, askForPassword, askForSecret, bugReport, buildToolsCheck, buildToolsExec, buildToolsInstall, callFun, convertTheme, createProjectTemplate, dictionariesPath, documentClose, documentNew, documentSave, documentSaveAll, document_position, document_range, executeCommand, findFun, getActiveDocumentContext, getActiveProject, getConsoleEditorContext, getPersistentValue, getRStudioPackageDependencies, getSourceEditorContext, getThemeInfo, getThemes, getVersion, hasColorConsole, hasFun, highlightUi, initializeProject, insertText, is.document_position, is.document_range, isAvailable, jobAdd, jobAddOutput, jobAddProgress, jobRemove, jobRunScript, jobSetProgress, jobSetState, jobSetStatus, launcherAvailable, launcherConfig, launcherContainer, launcherC
In addition: Warning messages:
1: S3 methods ‘as.document_position.default’, ‘as.document_position.document_position’, ‘as.document_range.default’, ‘as.document_range.document_range’, ‘format.document_position’, ‘format.document_range’, ‘primary_selection.document_context’, ‘primary_selection.document_selection’, ‘print.document_context’, ‘print.document_position’, ‘print.document_range’, ‘print.document_selection’ were declared in NAMESPACE but not found 
2: S3 methods ‘as.document_position.default’, ‘as.document_position.document_position’, ‘as.document_range.default’, ‘as.document_range.document_range’, ‘format.document_position’, ‘format.document_range’, ‘primary_selection.document_context’, ‘primary_selection.document_selection’, ‘print.document_context’, ‘print.document_position’, ‘print.document_range’, ‘print.document_selection’ were declared in NAMESPACE but not found 
3: S3 methods ‘as.document_position.default’, ‘as.document_position.document_position’, ‘as.document_range.default’, ‘as.document_range.document_range’, ‘format.document_position’, ‘format.document_range’, ‘primary_selection.document_context’, ‘primary_selection.document_selection’, ‘print.document_context’, ‘print.document_position’, ‘print.document_range’, ‘print.document_selection’ were declared in NAMESPACE but not found 

解决方法是重新安装包rstudioapi，见r - Problem with loading tidyverse on a Windows computer - Stack Overflow