将`=`变成`<；-`仅使用基本R 问题 将赋值等号转换为赋值箭头 仅使用基本R（无样式器或格式器） 上下文

例子 输入：

f = function(x = 1){}

期望输出：

f <- function(x = 1){}

---

f发布在问题中，但不妨尝试一些SO pts：

library(magrittr)

raw_src <- "z = {f('#') # comment

x <- 5
y = 'test'
    }"

# so we can have some tasty parse data
first <- parse(text = raw_src, keep.source = TRUE)

# this makes a nice data frame of the tokenized R source including line and column positions of the source bits
src_info <- getParseData(first, TRUE)

# only care about those blasphemous = assignments
elements_with_equals_assignment <- subset(src_info, token == "EQ_ASSIGN")

# take the source and split it into lines
raw_src_lines <- strsplit(raw_src, "\n")[[1]]

# for as many instances in the data frame replace the = with <-
for (idx in 1:nrow(elements_with_equals_assignment)) {
  stringi::stri_sub(
    raw_src_lines[elements_with_equals_assignment[idx, "line1"]],
    elements_with_equals_assignment[idx, "col1"],
    elements_with_equals_assignment[idx, "col2"]
  ) <- "<-"
}

# put the lines back together and do the thing
parse(
  text = paste0(raw_src_lines, collapse="\n"),
  keep.source = FALSE
)[[1]] %>%
  deparse() %>%
  cat(sep = "\n")
## z <- {
##     f("#")
##     x <- 5
##     y <- "test"
## }

库（magrittr）
原始的src发布在问题中，但也可以尝试一些SO pts：

library(magrittr)

raw_src <- "z = {f('#') # comment

x <- 5
y = 'test'
    }"

# so we can have some tasty parse data
first <- parse(text = raw_src, keep.source = TRUE)

# this makes a nice data frame of the tokenized R source including line and column positions of the source bits
src_info <- getParseData(first, TRUE)

# only care about those blasphemous = assignments
elements_with_equals_assignment <- subset(src_info, token == "EQ_ASSIGN")

# take the source and split it into lines
raw_src_lines <- strsplit(raw_src, "\n")[[1]]

# for as many instances in the data frame replace the = with <-
for (idx in 1:nrow(elements_with_equals_assignment)) {
  stringi::stri_sub(
    raw_src_lines[elements_with_equals_assignment[idx, "line1"]],
    elements_with_equals_assignment[idx, "col1"],
    elements_with_equals_assignment[idx, "col2"]
  ) <- "<-"
}

# put the lines back together and do the thing
parse(
  text = paste0(raw_src_lines, collapse="\n"),
  keep.source = FALSE
)[[1]] %>%
  deparse() %>%
  cat(sep = "\n")
## z <- {
##     f("#")
##     x <- 5
##     y <- "test"
## }

库（magrittr）
raw_src可能是
sub（“=”，“输入可以是字符向量或语言对象，也可以是好的。
sub（）
将
x=1
替换为
x如果您的输入是字符向量，那么
sub（“=”，“可能是
sub（“=”，“输入可以是字符向量或语言对象，也可以是好的。
sub（）
将
x=1
替换为
x如果您的输入是字符向量，则
sub（“=”，“+1），但我可以用
”=”（zz，yy）将其打断
和
zz=yy=3
是的。我在GH杂志上提到了这一点。所以我不能享受所有的乐趣。太棒了，@hrbrmstr！谢谢！@Moody_mudscappper我刚刚在+1发表了你的评论，但我可以用
'='（zz，yy）来打断它
和
zz=yy=3
是的。我在GH杂志上提到了这一点。所以不能享受所有的乐趣。太棒了，@hrbrmstr！谢谢！@Moody_mudscapper我刚刚在上发表了你的评论。