lenient_parse

A Gleam library providing lenient parsing functions for converting strings to float and integer values. This package offers more flexible parsing than the standard Gleam functions, similar to Python’s built-in float() and int() functions.

Installation

gleam add lenient_parse

import lenient_parse
import gleam/io

pub fn main() {
  // --- Float parsing

  // Parse a string containing an integer
  "1" |> lenient_parse.to_float |> io.debug
  // Ok(1.0)

  // Parse a string containing a negative float
  "-5.001" |> lenient_parse.to_float |> io.debug
  // Ok(-5.001)

  // Parse a more complex float with scientific notation
  "-1_234.567_8e-2" |> lenient_parse.to_float |> io.debug
  // Ok(-12.345678)

  // --- Integer parsing

  // Parse a string containing an integer
  "123" |> lenient_parse.to_int |> io.debug
  // Ok(123)

  // Parse a string containing a negative integer with surrounding whitespace
  "  -123  " |> lenient_parse.to_int |> io.debug
  // Ok(-123)

  // Parse a string containing an integer with underscores
  "1_000_000" |> lenient_parse.to_int |> io.debug
  // Ok(1000000)

  // Parse a binary string
  "1000_0000" |> lenient_parse.to_int_with_base(base: 2) |> io.debug
  // Ok(128)

  // Parse a hexadecimal string
  "DEAD_BEEF" |> lenient_parse.to_int_with_base(base: 16) |> io.debug
  // Ok(3735928559)
}

Developer Setup

To run the tests for this package, you’ll need to install uv.