Testing for
loop termination using an equality operator (==
and !=
) is dangerous, because it could set up an
infinite loop. Using a broader relational operator instead casts a wider net, and makes it harder (but not impossible) to accidentally write an
infinite loop.
for (int i = 1; i != 10; i += 2) // Noncompliant. Infinite; i goes from 9 straight to 11. { //... }
for (int i = 1; i <= 10; i += 2) // Compliant { //... }
Equality operators are ignored if the loop counter is not modified within the body of the loop and either:
Equality operators are also ignored when the test is against null
.
for (int i = 0; arr[i] != null; i++) { // ... } for (int i = 0; (item = arr[i]) != null; i++) { // ... }