Javascript set const variable inside of a try block

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Is it possible in ES6 to set a variable inside of a try{} using const in strict mode?

'use strict';

const path = require('path');

try {
    const configPath = path.resolve(process.cwd(), config);
} catch(error) {
    //.....
}

console.log(configPath);

This fails to lint because configPath is defined out of scope. The only way this seems to work is by doing:

'use strict';

const path = require('path');

let configPath;
try {
    configPath = path.resolve(process.cwd(), config);
} catch(error) {
    //.....   
}

console.log(configPath);

Basically, is there any way to use const instead of let for this case?

Answer

Declaring a variable as const requires you to immediately point it to a value and this reference cannot be changed.

Meaning you cannot define it at one place (outside of try) and assign it a value somewhere else (inside of try).

const test; // Syntax Error
try {
  test = 5; 
} catch(err) {}

On the other hand, both creating it and giving it a value within the try block is fine.

try {
  const test = 5; // this is fine
} catch(err) {}

However, const is block-scoped, like let, so if you do create it and give it a value within your try block, it will only exist within that scope.

try {
  const test = 5; // this is fine
} catch(err) {}
console.log(test); // test doesn't exist here

Therefore, if you need to access this variable outside of the try, you must use let:

let configPath;
try {
   configPath = path.resolve(process.cwd(), config);
} catch(error) {
    //.....   
}

console.log(configPath);

Alternatively, although probably more confusingly, you can use var to create a variable within the try and use it outside of it because var is scoped within the function, not the block (and gets hoisted):

try {
   var configPath = path.resolve(process.cwd(), config);
} catch(error) {
    //.....   
}

console.log(configPath);


Source: stackoverflow