rlang (version 0.2.2)

fn_env: Return the closure environment of a function

Description

Closure environments define the scope of functions (see env()). When a function call is evaluated, R creates an evaluation frame (see ctxt_stack()) that inherits from the closure environment. This makes all objects defined in the closure environment and all its parents available to code executed within the function.

Usage

fn_env(fn)
fn_env(x) <- value

Arguments

fn, x

A function.

value

A new closure environment for the function.

Details

fn_env() returns the closure environment of fn. There is also an assignment method to set a new closure environment.

Examples

# NOT RUN {
env <- child_env("base")
fn <- with_env(env, function() NULL)
identical(fn_env(fn), env)

other_env <- child_env("base")
fn_env(fn) <- other_env
identical(fn_env(fn), other_env)
# }