peter

function nil(value) {
  return value === undefined || value === null
}

function notNil(value) {
  return !nil(value)
}

function empty(value) {
  if (nil(value)) {

peter

Java vs Python

Split String

Java:

String numberString = "1,2,3,4,5";
int[] numbers = Arrays.stream(numberString.split(",")).mapToInt(Integer::parseInt).toArray();

peter

Python runtime type checks with decorator

# This modules provides pre/post conditions for python functions via the @typeSpec decorator

from functools import reduce

def compact(d):
    return {k: v for k, v in d.items() if v != None}

peter

Static vs Dynamic Typing for JSON Handling

The point of comparison here is a function that filters some JSON based on on an access property set in a JSON schema. See Haskell vs Clojure for an interesting similar comparison.

Scala

The Scala code uses the circe library for Json handling:

peter

S3 Direct JavaScript Upload

TypeScript Code

S3 client module:

import * as AWS from 'aws-sdk'

export const REGION = 'eu-west-1'

peter

Untyped Scala vs Properly Typed Scala vs Dynamic Typing

The point of comparison here is a simple function that looks up a string key in a nested map/dictionary (JSON data from the payload/claims of a JWT token) and returns the given key if it's there and None/nil otherwise.

Scala (Without Proper Types)

Original function:

def verifyPartner(partner: String, payload: Map[String, java.lang.Object]): Either[String, String] = {

peter

export class User {
  id: string
  country: string
  email: string
  name: string
  tags: string[]
  verified: boolean
  active: boolean
  locale: string
  openIds: any

peter

{
  "compilerOptions": {
    "target": "es5",
    "module": "commonjs",
    "moduleResolution": "node",
    "sourceMap": true,
    "emitDecoratorMetadata": true,
    "experimentalDecorators": true,
    "lib": [ "es2015", "dom" ],
    "noImplicitAny": true,

peter

{
    "editor.fontSize": 14,
    "editor.tabSize": 2,
    "editor.detectIndentation": false,
    "editor.insertSpaces": true,
    "files.trimTrailingWhitespace": true,
    "files.exclude": {
        "**/.git": true,
        "**/.svn": true,
        "**/.hg": true,

peter

const R = require('ramda')

function pathString(path: string[]): string {
  return path.join('.')
}

function valueType(value: any): string {
  if (value === undefined) {
    return 'undefined'
  } else if (value === null) {