Reason #61 • March 2nd, 2026

File.read

When programming, reading files is about as common an operation as one can imagine. Wouldn't it be great if there were a simple, obvious, zero-ceremony way to read the contents of a file into a string?

Yes!

Ruby
content = File.read("path/to/file.txt")
JavaScript
const fs = require('fs');
const content = fs.readFileSync('path/to/file.txt', 'utf-8');

What about other languages?

For additional comparison, I asked ChatGPT to provide the most basic/idiomatic ways to read files in a couple of other languages and added them here in rough order of verbosity:

C
#include <stdio.h>
#include <stdlib.h>

char* read_file_utf8(const char* path) {
  FILE* f = fopen(path, "rb");
  if (!f) return NULL;

  if (fseek(f, 0, SEEK_END) != 0) { fclose(f); return NULL; }
  long n = ftell(f);
  if (n < 0) { fclose(f); return NULL; }
  rewind(f);

  char* buf = (char*)malloc((size_t)n + 1);
  if (!buf) { fclose(f); return NULL; }

  size_t read = fread(buf, 1, (size_t)n, f);
  fclose(f);
  buf[read] = '\0';
  return buf; // caller frees
}
C++
#include <fstream>
#include <iterator>
#include <string>

std::ifstream in(path, std::ios::binary);
std::string content((std::istreambuf_iterator<char>(in)), std::istreambuf_iterator<char>{});
Java
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.Path;

String content = Files.readString(Path.of(path), StandardCharsets.UTF_8);
C#
using System.IO;
using System.Text;

string content = File.ReadAllText(path, Encoding.UTF8);
Go
import os
bytes, err := os.ReadFile("path/to/file.txt")
if err != nil {
    // handle error
}
content := string(bytes)
Haskell
import qualified Data.ByteString as BS
import qualified Data.Text as T
import qualified Data.Text.Encoding as TE

content :: T.Text
content = either (error . show) id . TE.decodeUtf8' =<< BS.readFile path
Rust
use std::fs;

let content: String = fs::read_to_string(path)?;
Python
from pathlib import Path

content = Path(path).read_text(encoding="utf-8")
Clojure
(def content (slurp path :encoding "UTF-8"))
Elixir
content = File.read!(path)
Crystal
content = File.read(path)

Somehow, only Elixir and Crystal provide similarly straightforward APIs for reading files, and they did so by copying Ruby!

History

File.read was added to Ruby in version 1.8 in 2001.