extract_functions: Extract function calls from character vector of R code

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Extract function calls from character vector of R code

Description

This function finds all of the R functions in a character vector of R code. For R scripts, first use readLines() or readr::read_file() to import the script into a character vector. For R Markdown or Quarto documents, first use extract_code() to find all of the R code in code blocks. The character vector can then be passed to extract_functions() to find all of the functions. By default, all instances of functions are returned. To omit duplicate functions, set duplicates = FALSE.

Usage

extract_functions(code, duplicates = TRUE)

Arguments

code	Object that contains R code.
duplicates	Logical indicating whether to include duplicates of functions or whether to remove duplicates (default is TRUE, which includes duplicates).

Value

Returns character vector of function names without parentheses (e.g., it returns "library" rather than "library()") included in R code.

Note

This function is adapted from one Yihui Xie posted at https://yihui.org/en/2023/01/func-call/.

See Also

Other functions for extracting code and functions: build_functions_df(), extract_code()

Examples

extract_functions(extract_code(
  "https://raw.githubusercontent.com/JeffreyRStevens/flashr/refs/heads/main/README.Rmd"
))

flashr documentation built on June 8, 2025, 11:39 a.m.