escape-triple-quoted.R

# function for parsing strings where quotes are not escaped but nested inside triple-quotes

escape_triple_quoted = function(j){
  j_split = strsplit(j, '"{3}')[[1]]
  f = seq_along(j_split) %% 2 == 0  # filter
  j_split[f] = gsub('"', '\\\\"', j_split[f])
  paste(j_split, collapse = '"')
}

# Usage

j0 = '[
  {
      "A" : "no quoted bits"
  },
  {
    "A" : """this contains: "quoted" bits""",
    "B" : "no quoted bits"
  },
  {
    "A" : "no quoted bits",
    "B" : """this contains: "quoted" and "more quoted" bits"""
  }
]'

# clearly this will fail
jsonlite::fromJSON(j0)
#> Error: parse error: after key and value, inside map, I expect ',' or '}'
#>            bits"   },   {     "A" : """this contains: "quoted" bits"""
#>                      (right here) ------^

escape_triple_quoted(j0) |> jsonlite::fromJSON()
#>                              A                                              B
#> 1               no quoted bits                                           <NA>
#> 2 this contains: "quoted" bits                                 no quoted bits
#> 3               no quoted bits this contains: "quoted" and "more quoted" bits