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open Ast
(*
--# Read Parquet file
--#
--# Reads a DataFrame from a Parquet file using the native parquet-glib reader.
--#
--# @name read_parquet
--# @param path :: String Path or URL to the Parquet file.
--# @return :: DataFrame The loaded data.
--# @example
--# df = read_parquet("data.parquet")
--# @family dataframe
--# @seealso read_csv, read_arrow
--# @export
*)
let register env =
Env.add "read_parquet"
(make_builtin ~name:"read_parquet" 1 (fun args _env ->
match args with
| [VString path] ->
(match Arrow_io.read_parquet path with
| Ok table -> VDataFrame { arrow_table = table; group_keys = [] }
| Error msg -> Error.make_error FileError msg)
| [VNA _] -> Error.type_error "Function `read_parquet` expects a String path, got NA."
| [_] -> Error.type_error "Function `read_parquet` expects a String path."
| _ -> Error.arity_error_named "read_parquet" 1 (List.length args)
))
env