有没有办法找出我在我的包中使用的 base、stats 等包功能需要哪个 R 版本？
例如，我使用自己的代码来获取剩余的 SD，然后将其替换为 stats::sigma()。但是，sigma() 需要 R 版本 >= 3.3。反过来，我的包应该依赖于 R >= 3.2，并且包检查和 CRAN 提交都没有警告我的说明文件中 R 依赖项的错误规范...
【问题讨论】：
startsWith() 是另一个候选者，我不知道它需要一个较晚的 R 版本。
标签： r dependencies package
似乎没有办法以可靠的方式以编程方式执行此操作。一般来说，最简单的方法是处理新闻。以下代码提取 NEWS 中包含“新功能”的所有句子：
library(data.table)
library(stringr)
db <- as.data.table(news())
db <- db[Category == "NEW FEATURES" & grepl("[Nn]ew function[^a]", Text), .(Text, Version)]
db[, Text := str_replace_all(Text, "\n", "")]
db[, Text := str_extract(Text, "[Nn]ew function.*?\\.(?=($| ))"), by = Version]
> db
Text Version
1: new function .valid.factor(). 3.4.0
2: New function check_packages_in_dir_details() in package tools for analyzing package-check log files to obtain check details. 3.4.0
3: New functions validEnc() and validUTF8() to give access to the validity checks for inputs used by grep() and friends. 3.3.0
4: New function strrep() for repeating the elements of a character vector. 3.3.0
5: New function grouping() returns a permutation that stably rearranges data so that identical values are adjacent. 3.3.0
6: New function .traceback() returns the stack trace which traceback() prints. 3.3.0
7: New functions makevars_user() and makevars_site() in package tools to determine the location of the user and site specific Makevars files for customizing package compilation. 3.3.0
8: New function dir.exists() in package base to test efficiently whether one or more paths exist and are directories. 3.2.0
9: new function debuggingState() has been added, allowing to temporarily turn off debugging. 3.2.0
10: New function extSoftVersion() to report on the versions of third-party software in use in this session. 3.2.0
11: New function isNamespaceLoaded() for readability and speed. 3.2.0
12: New function trimws() for removing leading/trailing whitespace. 3.2.0
13: New function hsearch_db() in package utils for building and retrieving the help search database used by help.search(), along with functions for inspecting the concepts and keywords in the help search database. 3.2.0
14: New function .getNamespaceInfo(), a no-check version of getNamespaceInfo() mostly for internal speedups. 3.2.0
15: New function toTitleCase() in package tools, tailored to package titles. 3.2.0
16: New function pcre_config() to report on some of the configuration options of the version of PCRE in use. 3.1.3
17: New function icuGetCollate() to report on the ICU collation locale in use (if any). 3.1.2
18: new function promptImport(), to generate a help page for a function that was imported from another package (and presumably re-exported, or help would not be needed). 3.1.1
19: New function anyNA(), a version of any(is.na(.)) which is fast for atomic vectors, based on a proposal by Tim Hesterberg. 3.1.0
20: new function find_gs_cmd() in the tools package to locate a GhostScript executable. 3.1.0
21: New functions cospi(x), sinpi(x), and tanpi(x), for more accurate computation of cos(pi*x), etc, both in R and the C API. 3.1.0
22: New function agrepl() which like grepl() returns a logical vector. 3.1.0
23: new function, La_version(), to report the version of LAPACK in use. 3.0.3
24: New functions cite() and citeNatbib() have been added, to allow generation of in-text citations from "bibentry" objects. 3.0.0
25: new function rep_len() analogous to rep.int() for when speed is required (and names are not). 3.0.0
26: New functions bitwNot(), bitwAnd(), bitwOr() and bitwXor(), using the internal interfaces previously used for classes "octmode" and "hexmode". 3.0.0
【讨论】：