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import React from 'react'
import useApp from './useApp'
import './styles.css'

const Input = (props) => (
  <input
    type="file"
    accept="image/*"
    name="img-loader-input"
    multiple

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const triggerInput = (e) => {
  e.persist()
  inputRef.current.click()
}

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return {
  ...state,
  onSubmit,
  onChange,
  triggerInput,
}

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const useApp = ({ urls }) => {
  const [results, setResults] = React.useState(null)

  const promises = urls.map((url) => axios.get(url))

  React.useEffect(() => {
    Promise.all(promises).then(setResults)
  }, [])

  return { results }

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const promises = React.useMemo(() => {
  return urls.map((url) => axios.get(url))
}, [urls])

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import React from 'react'

const UserContext = React.createContext({
  user: {
    firstName: 'Kelly',
    email: '[email protected]',
  },
  activated: true,
})

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const authReducer = (state, action) => {
  switch (action.type) {
    case 'set-authenticated':
      return { ...state, authenticated: action.authenticated }
    default:
      return state
  }
}

export default authReducer

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function combineWords(word) {
  return function(anotherWord) {
    return function(andAnotherWord) {
      return `${word} ${anotherWord} ${andAnotherWord}`
    }
  }
}

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const result = combineWords('hello,')('good')('morning')
console.log(result)

// result: 'hello, good morning'

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let greet = combineWords('wow!')
greet = greet('nice')

console.log(greet('jacket'))
console.log(greet('shoes'))
console.log(greet('eyes'))
console.log(greet('socks'))
console.log(greet('hat'))
console.log(greet('glasses'))
console.log(greet('finger nails'))