javascript & Uncaught TypeError: arr is not iterable bug All In One

javascript & Uncaught TypeError: arr is not iterable bug All In One

error

  function compute(arr) {
    const [left, symbol, right] = arr;
    switch (symbol) {
      case "*":
        result =  left * right;
        break;
      case "/":
        result =  left / right;
        break;
      case "+":
        result =  left + right;
        break;
      case "-":
        result = left - right;
        break;
    }
    return result;
  }

const arr1 = [3, "+"];
const arr2 = [2, "*", 3];

compute(arr1.push(compute(arr2)));
//  ❌ Uncaught TypeError: arr is not iterable

const [left, symbol, right] = arr2;
// ✅

compute(arr2);
// 6
arr1.push(6);
// 3, 返回 arr1.length

compute(3);
//  ❌ Uncaught TypeError: arr is not iterable

solution

  function compute(arr) {
    const [left, symbol, right] = arr;
    switch (symbol) {
      case "*":
        result =  left * right;
        break;
      case "/":
        result =  left / right;
        break;
      case "+":
        result =  left + right;
        break;
      case "-":
        result = left - right;
        break;
    }
    return result;
  }

const arr1 = [3, "+"];
const arr2 = [2, "*", 3];

arr1.push(compute(arr2));
compute(arr1);

What went wrong?

The value which is given as the right-hand side of for...of, or as argument of a function such as Promise.all or TypedArray.from, or as the right-hand side of an array destructuring assignment, is not an iterable object.
An iterable can be a built-in iterable type such as Array, String or Map, a generator result, or an object implementing the iterable protocol.

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Errors/is_not_iterable

LeetCode

227. Basic Calculator II

https://leetcode.com/problems/basic-calculator-ii/

function calculate(s: string): number {
  const symbols = ["*", "/", "+", "-"];
  // remove spaces
  // s = s.replaceAll(/\s/g, ``);
  s = s.replace(/\s/g, ``);
  if(![...s].some(i => symbols.includes(i))) {
    return parseInt(s);
  }
  const stack = [];
  let temp = ``;
  // for(let c of s) {
  //   if(!symbols.includes(c)) {
  //     temp += c;
  //   } else {
  //     stack.push(parseInt(temp));
  //     stack.push(c);
  //     temp = ``;
  //   }
  //   if(temp) {
  //     stack.push(parseInt(temp));
  //   }
  // }
  for (let i = 0; i < s.length; i++) {
    const c = s[i];
    if(!symbols.includes(c)) {
      temp += c;
    } else {
      stack.push(parseInt(temp));
      stack.push(c);
      temp = ``;
    }
    if(temp && i === s.length - 1) {
      stack.push(parseInt(temp));
    }
  }
  console.log(`stack =`, stack);
  let total = 0;
  let arr1 = [];
  let arr2 = [];
  let isMD = false;
  for(let i of stack) {
    // 运算优先级 +- ? */
    if(!symbols.includes(i)) {
      if(isMD) {
        arr2.push(i);
      } else {
        arr1.push(i);
      }
    } else {
      if(["+", "-"].includes(i)) {
        isMD = false;
        arr1.push(i);
      }
      if(["*", "/"].includes(i)) {
        isMD = true;
        let left = arr1.pop();
        arr2.push(left);
        arr2.push(i);
      }
    }
  }
  // function compute(arr) {
  //   const [left, symbol, right] = arr;
  //   switch (symbol) {
  //     case "*":
  //       return left * right;
  //     case "/":
  //       return left / right;
  //     case "+":
  //       return left + right;
  //     case "-":
  //       return left - right;
  //       // break;
  //   }
  // }
  function compute(arr) {
    const [left, symbol, right] = arr;
    let result = 0;
    switch (symbol) {
      case "*":
        result = left * right;
        break;
      case "/":
        result = Math.floor(left / right);
        break;
      case "+":
        result =  left + right;
        break;
      case "-":
        result = left - right;
        break;
    }
    return result;
  }
  console.log(`arr2 =`, arr2);
  if(arr1.length && arr2.length) {
    arr1.push(compute(arr2));
    console.log(`arr1 =`, arr1);
    total += compute(arr1);
  } else if(arr1.length) {
    // ❌
    total += compute(arr1);
  } else if(arr2.length) {
    total += compute(arr2);
  }
  // total += compute(arr1.push(compute(arr2)));
  return total;
};

/*

Line 3: Char 9: error TS2550: Property 'replaceAll' does not exist on type 'string'. Do you need to change your target library? Try changing the 'lib' compiler option to 'es2021' or later.

arr = [3, "+", 2, "*", 3];

"42"

*/

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