continue

continue skips the remainder of the current loop iteration and jumps to the next iteration of the nearest enclosing loop.

Surface Syntax#

continue;

Notes:

• continue is a statement, terminated by a semicolon.

Semantics#

When executed inside a loop body, continue;:

• stops executing the remainder of the current iteration’s body, and
• transfers control to the loop’s “next iteration” point:
• for loop, this means jumping to the start of the loop body.
• for while, this means re-evaluating the loop condition.
• for for, this means advancing to the next iteration (and for C-style for loops, executing the loop step before re-checking the loop condition).

Example:

fn main () -> int {
  let mut i: int = 0;
  while i < 10 {
    i += 1;
    if i == 5 {
      continue; // skips the return below for i == 5
    }
    // More work could happen here.
  }
  return 0;
}

In nested loops, continue applies to the nearest loop:

fn main () -> int {
  while true {
    while true {
      continue; // continues the inner loop
    }
  }
  return 0;
}

Type Checking Rules#

• continue is only permitted inside a loop body.
• A continue outside a loop is a type-check error (diagnostics, E2008).

Notes#

• continue; is accepted inside loops (loop, while, and for) and lowered end-to-end.
• continue; outside a loop is rejected (E2008).

Example that uses continue in the Supported forms:

Common Pitfalls#

• Forgetting the semicolon (continue is a statement).
• Expecting continue to exit the loop (it does not; use break).
• Using continue outside a loop (rejected, E2008).