v4 Control Flow: for, break/continue, && / ||

Why v4?

We already have arrays, maps, closures, and GC. Now we add the control-flow features that make real programs less clunky:

• for loops with init/cond/post
• break and continue
• short-circuit boolean operators && and ||

These features are "language feel" improvements and force deeper compiler reasoning.

1) New syntax

for loop

for (init; cond; post) {
  ...
}

• init runs once before the loop.
• cond is checked before each iteration.
• post runs after each iteration.
• Any part can be omitted.

break / continue

break;     // exit the nearest loop
continue;  // skip to the next iteration

logical operators

a && b   // false if a is falsey, otherwise uses b

c || d   // true if c is truthy, otherwise uses d

We keep the result as a boolean (not the original value).

2) Semantics at a glance

• break / continue are only valid inside loops.
• for introduces a loop scope (init vars live only inside the loop).
• && / || are short-circuiting and use truthiness.

3) Compiler implications

• for can be lowered into a while-like shape.
• break / continue need jump patching.
• && / || require jump-based short-circuit codegen.

4) Our goal

Keep the implementation readable, testable, and modular. This is about clarity, not clever tricks.