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No trivial switch statements

ID: cpp/trivial-switch Kind: problem Security severity: Severity: recommendation Precision: high Tags: - maintainability - readability - external/jsf Query suites: - cpp-security-and-quality.qls

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The following forms of switch statement are considered trivial:

  1. No cases at all.

  2. Just a default case.

  3. Just one non-default case.

  4. A default case and one non-default case.

Recommendation

Either the switch statement should be replaced with a simpler control flow structure, or it should be extended to handle more cases. Each trivial form has a different replacement:

  1. If there are no cases, the switch statement can be removed.

  2. If there is just one default case, the switch keyword, the default keyword, and the subsequent colon can all be removed.

  3. If there is just one non-default case, the switch statement can be turned into an if statement.

  4. If there is one default case and one non-default case, the switch statement can be turned into an if/else statement.

Example

int f() { int val = 0; switch(val) { //wrong, use an if instead case 0: //... default: //... } switch(val) { //correct, has 2 cases and a default case 0: //... case 1: //... default: //... } }

References