Chapter 10: "Handling Errors" errata

itaid

"Try/Catch" subsection

Erroneous invocation of result() in the code snippets below:

try {
  const result = doTask(4)
  result()
  console.log('result', result)
} catch (err) {
  if (err instanceof TypeError) {
    console.error('wrong type')
  } else if (err instanceof RangeError) {
    console.error('out of range')
  } else if (err.code === 'ERR_MUST_BE_EVEN') {
    console.error('cannot be odd')
  } else {
    console.error('Unknown error', err)
  }
}
 
try {
  const result = doTask(4)
  result()
  console.log('result', result)
} catch (err) {
  if (err.code === 'ERR_AMOUNT_MUST_BE_NUMBER') {
    console.error('wrong type')
  } else if (err.code === 'ERRO_AMOUNT_MUST_EXCEED_ZERO') {
    console.error('out of range')
  } else if (err.code === 'ERR_MUST_BE_EVEN') {
    console.error('cannot be odd')
  } else {
    console.error('Unknown error', err)
  }
}

"Rejections" subsection

The doTask function does not "codify" TypeError and RangeError.

function doTask (amount) {
  return new Promise((resolve, reject) => {
    if (typeof amount !== 'number') {
      reject(new TypeError('amount must be a number'))
      return
    }
    if (amount <= 0) {
      reject(new RangeError('amount must be greater than zero'))
      return
    }
    if (amount % 2) {
      reject(new OddError('amount'))
      return
    }
    resolve(amount/2)
  })
}
 
 
doTask(3)
  .then((result) => {
    console.log('result', result)
  })
  .catch((err) => {
    if (err.code === 'ERR_AMOUNT_MUST_BE_NUMBER') {
      console.error('wrong type')
    } else if (err.code === 'ERRO_AMOUNT_MUST_EXCEED_ZERO') {
      console.error('out of range')
    } else if (err.code === 'ERR_MUST_BE_EVEN') {
      console.error('cannot be odd')
    } else {
      console.error('Unknown error', err)
    }
 
  })

d.m.c

thanks will take a look