Java 21: Unnamed variables with underscore

Use _ for variables you must declare but never use, clarifying intent.

var counts = new int[]{10, 20, 30};
int total = 0;
for (var _ : counts) {
    total += 5;   // we only care how many, not the value
}
System.out.println("total = " + total);

total = 15

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Published 2026-07-26