E0173: cannot assign to loop variable in for of/in loop
There are three kinds of for loops: C-style for loops (;), for-in
loops, and for-of loops. It is a syntax error to write a for-in or
for-of loop which declares a variable with const or let and initializes
the variable:
function firstItem(collection) {
for (const item = null of collection) {
break;
}
return item;
}
To fix this error, declare the variable outside the for-in or for-of
loop with let:
function firstItem(collection) {
let item = null;
for (item of collection) {
break;
}
return item;
}
Introduced in quick-lint-js version 0.4.0.