Add `combine_lexicon`

[Tyler Rinker]

A function to take lexicons (named) combine them together removing dupes (for lookups dupes replaced by first value)

combine_lexicon <- function(lexicons, ask.dupes = FALSE, ...){

    ## check that all lexicons are of the same type (grouped together)
    ## manual mapping?  or by naming convention?

    ## get internal data
    dats <- lapply(lexicons, function(x) eval(parse(text = paste0('lexicon::', x))))

    ## handling for atomic vs tabular
    if (is.atomic(dats)) {

    } else {

        ## for tabular lexicons


        if (ask.dupes){
            ## interactively as for which dupe to keep
        } else {
            ## keep first dupe
        }

        ## handling for unequal nuber of columns
        ## handling for data.table keyed lookups
    }

}

[Tyler Rinker]

See: https://github.com/trinker/sentimentr/blob/master/R/combine_data.R

[Tyler Rinker]

For tables use: data.table::rbind.list (fill=TRUE)

Also remove duplicate rows.

[Tyler Rinker]

This really isn't any better than using c or rbind.list