Replace multiple statements-CodePudding

Given the following code:

if (CONDITION1) {
  if (CONDITION2) {
    if (CONDITION3) {
      if (CONDITION4) {
        if (CONDITION5) {

        } else {
          return ('STOP IN CONDITION5')
        }
      } else {
        return ('STOP IN CONDITION4')
      }
    } else {
      return ('STOP IN CONDITION3')
    }
  } else {
    return ('STOP IN CONDITION2')
  }
} else {
  return ('STOP IN CONDITION1')
}

I need to replace these multiple if statements for some other code using good practices and for cleaner reading for other people in future.

CodePudding user response：

You could flatten this by testing for not condition:

function doStuff() {
  if (!CONDITION1) {
    return ('STOP IN CONDITION1')
  }

  if (!CONDITION2) {
    return ('STOP IN CONDITION2')
  }

  if (!CONDITION3) {
    return ('STOP IN CONDITION3')
  }

  if (!CONDITION4) {
    return ('STOP IN CONDITION4')
  }

  if (!CONDITION5) {
    return ('STOP IN CONDITION5')
  }
}

Note: in between the ifs you could add code for condition true.

CodePudding user response：

This has already been answered and I wouldn't recommend this version (linters probably complain, flat if statements are fine) but I'm throwing it in there to show another possibility.

You can potentially use a switch statement and add your conditions to each case:

const CONDITION1 = 1 > 2
const CONDITION2 = 2 < 1

const run = () => {
  switch(true) { // always evaluate this switch
    case !CONDITION1: 
      return 'STOP IN CONDITION1'
    case !CONDITION2:
      return 'STOP IN CONDITION1'
    // etc...
  }
}

console.log(run())