tysv

gleam add tysv

Standard CSV

import gleam/float
import gleam/int
import gleam/string
import tysv
import tysv/text

const data = "Vanilla,23,0.5
Strawberry,24,0.75
Mango,34,1.75"

const rows = [
  #("Vanilla", 23, 0.5),
  #("Strawberry", 24, 0.75),
  #("Mango", 34, 1.75),
]

pub fn standard_csv() {
  // Build typed list from CSV
  assert Ok(rows)
    == tysv.build({
      use flavor <- tysv.parsed
      use price <- tysv.parsed
      use kg <- tysv.parsed
      #(flavor, price, kg)
    })
    |> tysv.col(Ok)
    |> tysv.col(int.parse)
    |> tysv.col(float.parse)
    |> tysv.from(data)

  // Build CSV from typed list
  assert data
    == text.build(fn(row) {
      let #(flavor, price, kg) = row
      [flavor, int.to_string(price), float.to_string(kg)]
    })
    |> text.from(rows)
}
}

Skip Header

// Dependencies and constants from the standard case are omitted for brevity.

pub fn skip_header() {
  let data = "Flavor,Price,Kg\n" <> data

  // Build typed list from CSV (with header)
  assert Ok(rows)
    == tysv.build({
      use flavor <- tysv.parsed
      use price <- tysv.parsed
      use kg <- tysv.parsed
      #(flavor, price, kg)
    })
    |> tysv.col(Ok)
    |> tysv.col(int.parse)
    |> tysv.col(float.parse)
    |> tysv.skip_header(True)
    |> tysv.from(data)

  // Build CSV (with header) from typed list
  assert data
    == text.build(fn(row) {
      let #(flavor, price, kg) = row
      [flavor, int.to_string(price), float.to_string(kg)]
    })
    |> text.headers(["Flavor", "Price", "Kg"])
    |> text.from(rows)
}

Custom Separators

// Dependencies and constants from the standard case are omitted for brevity.

pub fn custom_separators() {
  let data =
    string.replace(data, ",", ";")
    |> string.replace("\n", "|")

  // Build typed list from CSV (with custom separators)
  assert Ok(rows)
    == tysv.build({
      use flavor <- tysv.parsed
      use price <- tysv.parsed
      use kg <- tysv.parsed
      #(flavor, price, kg)
    })
    |> tysv.col(Ok)
    |> tysv.col(int.parse)
    |> tysv.col(float.parse)
    |> tysv.col_sep(";")
    |> tysv.row_sep("|")
    |> tysv.from(data)

  // Build CSV (with custom separators) from typed list
  assert data
    == text.build(fn(row) {
      let #(flavor, price, kg) = row
      [flavor, int.to_string(price), float.to_string(kg)]
    })
    |> text.col_sep(";")
    |> text.row_sep("|")
    |> text.from(rows)
}

Further documentation can be found at https://hexdocs.pm/tysv.

Development

gleam test  # Run the tests

Provenance

All code in this project is written naturally. No AI generation or assistance is used to implement any functionality.

LICENSE

tysv is made available under the terms of the EUPL-1.2 License.