Examples for 'rlang::parse_expr'


Parse R code

Aliases: parse_expr parse_exprs parse_quo parse_quos

Keywords:

### ** Examples

# parse_expr() can parse any R expression:
parse_expr("mtcars %>% dplyr::mutate(cyl_prime = cyl / sd(cyl))")
mtcars %>% dplyr::mutate(cyl_prime = cyl/sd(cyl))
# A string can contain several expressions separated by ; or \n
parse_exprs("NULL; list()\n foo(bar)")
[[1]]
NULL

[[2]]
list()

[[3]]
foo(bar)
# Use names to figure out which input produced an expression:
parse_exprs(c(foo = "1; 2", bar = "3"))
$foo
[1] 1

$foo
[1] 2

$bar
[1] 3
# You can also parse source files by passing a R connection. Let's
# create a file containing R code:
path <- tempfile("my-file.R")
cat("1; 2; mtcars", file = path)

# We can now parse it by supplying a connection:
parse_exprs(file(path))
[[1]]
[1] 1

[[2]]
[1] 2

[[3]]
mtcars

[Package rlang version 1.1.4 Index]