在 R 中使用 gsub 内部的函数

Question

我有

txt <- "{a} is to {b} what {c} is to {d}"
key <- c(a='apple', b='banana', c='chair', d='door')
fun <- function(x) key[x]

我想快速转换txt为key：

"apple is to banana what chair is to door"

我知道我可以gsub像这样重复使用（或类似的东西）：

for (v in names(key)) txt <- gsub(sprintf('{%s}',v), fun(v), txt, fixed = TRUE)
txt
# [1] "apple is to banana what chair is to door"

但我的txt和key都很长，所以上面是有问题的。我想知道是否有更快的方法，例如：

gsub(sprintf('{%s}',names(key)), key, fixed = TRUE) # Does not work
gsub('\\{(a|b|c|d)\\}', fun(...), txt, fixed = TRUE) # Does not work

是否可以？谢谢。

Answer 1

我们可以glue在将 key 的元素创建为对象后使用

list2env(as.list(key), .GlobalEnv)
glue::glue(txt)

-输出

apple is to banana what chair is to door

如果我们不想在全局环境中创建对象，也可以在 the 中添加key[with ，然后使用gsub{}glue

glue::glue(gsub("\\{([^}]+)\\}", "{key['\\1']}", txt))
apple is to banana what chair is to door

或者正如 @Robert Hacken 在评论中提到的，.envir会更紧凑

glue::glue(txt, .envir=as.list(key))
apple is to banana what chair is to door

Answer 2

和glue_data()：

library(glue)
glue_data(key, txt)
# apple is to banana what chair is to door

在 R 中使用 Python 的原始示例：

library(reticulate)
list2env(as.list(key), envir = .GlobalEnv)
py_run_string('res = f"{r.a} is to {r.b} what {r.c} is to {r.d}"')
py$res
# "apple is to banana what chair is to door"