Tomas Valenta ValentaTomas

Building @e2b-dev

ValentaTomas / set_once.go

Created November 21, 2024 02:13

Thread-safe way to wait and propagate result/error to multiple places.

ValentaTomas / tunnel.go

Last active November 21, 2024 02:12

Resend the same value to several places without handling subscribers. (Not recommended for production.)

	type Tunnel[T any] struct {
	ch chan T
	}

	func (t *Tunnel[T]) Send(ctx context.Context, value T) error {
	select {
	case t.ch <- value:
	return nil
	case <-ctx.Done():
	return ctx.Err()

ValentaTomas / readLine.ts

Created July 11, 2024 06:33

Transform ReadableStream to async iterator of lines

	async function* readLines(stream: ReadableStream<Uint8Array>) {
	const reader = stream.getReader();
	let buffer = ''

	try {
	while (true) {
	const { done, value } = await reader.read();

	if (value !== undefined) {
	buffer += new TextDecoder().decode(value)

ValentaTomas / must.go

Created March 23, 2024 00:29

Go utility for ensuring a proper value that panics otherwise

	func Must[T any](obj T, err error) T {
	if err != nil {
	panic(err)
	}

	return obj
	}

ValentaTomas / ttl_cache.py

Last active January 8, 2024 11:39

Generic Python TTL cache that uses threads

	import threading
	import time

	from typing import Callable, TypeVar, Generic, Any, Dict, Tuple, List

	T = TypeVar("T")


	class TTLCache(Generic[T]):
	def __init__(

ValentaTomas / stopwatch.py

Created December 22, 2023 14:04

Measure execution time of a function

	def stopwatch():
	def decorator(func):
	def wrapper(args, *kwargs):
	start_time = time.time()
	result = func(args, *kwargs)
	end_time = time.time()
	elapsed_time = end_time - start_time
	print(f"time taken {elapsed_time: 2f}")
	return result

ValentaTomas / hash.ts

Last active October 13, 2023 20:13

Hash files

	import * as crypto from 'crypto'

	const delimiter = '\0'

	export function getFilesHash(files: { name: string; content: string }[]) {
	const shasum = crypto.createHash('sha1')

	files.forEach(({ name, content }) => {
	shasum.update(name)
	// Add delimiter to hash to prevent collisions between files where the join of the name and content is the same

ValentaTomas / random.sh

Last active October 4, 2024 07:51

Generate random string (the chars are only hex, not alphanumerical)

node -e "console.log(require('crypto').randomBytes(64).toString('hex'))"

ValentaTomas / id.py

Created August 4, 2023 14:26

Random alphanumeric id generator

	import random
	import string

	characters = string.ascii_letters + string.digits


	def id(length: int):
	return "".join(random.choices(characters, k=length))

ValentaTomas / deferred_future.py

Last active December 20, 2023 20:20

Deferred future for controlling async flow (there are existing asyncio features for doing this)

	import asyncio
	import json

	from typing import TypeVar, Generic, List

	T = TypeVar("T")


	class DeferredFuture(Generic[T]):
	def __init__(self):