mecab_tokenize

mecab_tokenize <- function(tbl, text_col, .drop=TRUE){
  loadNamespace("RMeCab")
  loadNamespace("tidyr")
  text_cname <- as.character(substitute(text_col))
  text <- tbl[[text_cname]]
  tokenize <- function(text){
    tokens <- unlist(RMeCab::RMeCabC(text))
    data.frame(.token = tokens, .pos = names(tokens))
  }
  if(.drop){
    tbl[[text_cname]] <- lapply(text, tokenize)
    token_col <- text_cname
  } else {
    tbl$.token <- lapply(text, tokenize)
    token_col <- ".token"
  }
  tidyr::unnest_(tbl, token_col)
}