sourceCpp: Source C++ Code from a File or String

Description

sourceCpp parses the specified C++ file or source code and looks for functions marked with the Rcpp::export attribute and RCPP_MODULE declarations. A shared library is then built and its exported functions and Rcpp modules are made available in the specified environment.

Usage

sourceCpp(file = "", code = NULL, env = globalenv(), 
          embeddedR = TRUE, rebuild = FALSE, 
          showOutput = verbose, verbose = getOption("verbose"))

Arguments

file

A character string giving the path name of a file

code

A character string with source code. If supplied, the code is taken from this string instead of a file.

env

Environment where the R functions and modules should be made available.

embeddedR

TRUE to run embedded R code chunks.

rebuild

Force a rebuild of the shared library.

showOutput

TRUE to print R CMD SHLIB output to the console.

verbose

TRUE to print detailed information about generated code to the console.

Value

Returns (invisibly) a list with two elements: ll{ functions Names of exported functions modules Names of Rcpp modules }

Details

If the code parameter is provided then the file parameter is ignored.

Functions exported using sourceCpp must meet several conditions, including being defined in the global namespace and having return types that are compatible with Rcpp::wrap and parameter types that are compatible with Rcpp::as. See the Rcpp::export documentation for more details. Content of Rcpp Modules will be automatically loaded into the specified environment using the Module and populate functions. If the source file has compilation dependencies on other packages (e.g. Matrix, RcppArmadillo) then an Rcpp::depends attribute should be provided naming these dependencies. It's possible to embed chunks of R code within a C++ source file by including the R code within a block comment with the prefix of /*** R. For example: /*** R

# Call the fibonacci function defined in C++ fibonacci(10)

Multiple R code chunks can be included in a C++ file. R code is sourced after the C++ compliation is completed so all functions and modules will be available to the R code.

Examples

Run this code

sourceCpp("fibonacci.cpp")

sourceCpp(code='
  #include <Rcpp.h>

  // [[Rcpp::export]]
  int fibonacci(const int x) {
    if (x == 0) return(0);
    if (x == 1) return(1);
    return (fibonacci(x - 1)) + fibonacci(x - 2);
  }'
)

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