R/opt_expand.R

In decisionpatterns/optigrab: Command-Line Parsing for an R World

#' Expand opts to full vector
#' 
#' Expand option vector to split names from values. This is an internal function 
#' and should generally not be called directly. 
#' 
#' @param opts character vector of arguments. (Default: [base::commandArgs()] )
#' 
#' @details 
#' 
#' `opt_expand` does two things: 
#' \itemize{
#'   #1. Removes values preceding and including `--args`. 
#'   #2. Splits and value containing an equal (`=``) sign. 
#' }
#' 
#' @seealso 
#'   - [opt_grab()] 
#'   - [base::commandArgs()]
#' 
#' @examples
#'   optigrab:::opt_expand()
#'   optigrab:::opt_expand( opts=c( "--foo", "bar") ) 
#'   
#' @note non-exported 

opt_expand <- function( opts=commandArgs() ) {
  
  opts <- opt_get_args(opts=opts)
  opts <- opt_split_args(opts=opts)
  
  # OPTION BUNDLING:
  # Based on style ... style$unbundle 
  # Expand dash-single-letter arguments.
  #  - splice in everything after -x as the value.
  #  wh.sd <- grep( "^-[^-]", opts ) 
  #  for( i in rev(wh.sd) ) {
  #    p <- sub( "^-[A-z]", "", opts[[i]] ) 
  #    append( opts, p, i ) 
  #  }
 
  return(opts) 
  
}