javascriptScope errorMedium

Counting matches always gives 0

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What it should do

countMatches(words, target) counts how many times target appears. Example: countMatches(["a", "b", "a"], "a") → 2.

What happens instead

countMatches(["a", "b", "a"], "a") returns 0.

function countMatches(words, target) {
    let count = 0;
    words.forEach(function (word) {
        let count = 0;
        if (word === target) {
            count = count + 1;
        }
    });
    return count;
}

Test a custom input to verify an edge case (e.g. empty lists, negative numbers, duplicates).

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This bug belongs to the scope and closure bugs pattern

Every callback reports the last value, a counter never increments, UnboundLocalError on a variable you can see.

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function countMatches(words, target) { let count = 0; words.forEach(function (word) { let count = 0; if (word === target) { count = count + 1; } }); return count; }

Counting matches always gives 0

What it should do

What happens instead

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Counting matches always gives 0

What it should do

What happens instead

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