switch
Function with Automatic Fallthrough Prevention
The switch
function enables multi-way branching based on the value of an expression. Unlike traditional C-style switch
statements, this variant automatically prevents fallthrough between cases and allows also for string comparisons , eliminating the need for break
statements at the end of each case.
Structure of the switch
Function
Components:
- Expression: An expression whose value is compared against the constants in each case block.
- Case Blocks: Each
case
distinguishes specific values for the expression. A match causes the associated code to execute. - Default Block: If no
case
matches the expression, the default block executes if provided.
Simple Example
value = 2;
switch (value) {
case (1)
lib.log(“Value is 1”);
case (2)
lib.log(“Value is 2”);
default
lib.log(“Value is something else”);
};
Explanation:
- Match and Isolate: When
value
is matched with acase
, only the corresponding block executes. The execution does not fall through to subsequent cases. - No
break
Needed: Automatic prevention of fallthrough simplifies function semantics and reduces boilerplate code.
Practical Use
- Control Flow Simplification: Automatically isolated cases reduce the risk of accidental fallthrough, making code more intuitive and less error-prone.
- Readability: Eliminates the potential clutter of required
break
statements after each case block, enhancing readability. - Maintainability: Reduces the probability of common errors associated with accidental fallthrough.