Merge multiple dataframes into a single "flat file"

mergeall_function.R

#############################################################################
# Two functions to merge a series of dataframes. This is needed if you want #
# to create a single "flat file" from multiple dataframes.                  #
#############################################################################

# Create an infix function %<<% that will merge two data frames. 
# Note Bene: 
# the dataframes to merge must have a shared column with the matched unique 
# id named "id".  You can vary this name by altering the code on line 12.
#
`%<<%` <- function(df1, df2){
  merge(df1, df2, by="id")  # Call the standard merge() function
}


mergeAll <- function(list_of_DFs){
  if(length(list_of_DFs) < 2){  # Check at least two dataframes to merge
    stop("There must be at least one dataframe for the function to work")
  }
  # Create a long string of all the dataframes to be merged, separating them
  # by the newly created infix function (%<<%)
  merge_command <- paste(list_of_DFs, collapse =' %<<% ')
  # Evaluate the expression
  eval(parse(text = merge_command)) 
}