R: Inject functions into the environment of 'evaluate()'

inject_funs {evaluate} | R Documentation

## Inject functions into the environment of `evaluate()`

### Description

Create functions in the environment specified in the `envir` argument of `evaluate()`. This can be helpful if you want to substitute certain functions when evaluating the code. To make sure it does not wipe out existing functions in the environment, only functions that do not exist in the environment are injected.

### Usage

    inject_funs(...)

### Arguments

`...` | Named arguments of functions. If empty, previously injected functions will be emptied.

### Note

For expert use only. Do not use it unless you clearly understand it.

### Examples

    library(evaluate)
    # normally you cannot capture the output of system
    evaluate("system('R --version')")

    # replace the system() function
    inject_funs(system = function(...) cat(base::system(..., intern = TRUE), sep = "\n"))

    evaluate("system('R --version')")

    inject_funs()  # empty previously injected functions

[Package evaluate version 0.11 Index]