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# goto

Perl 5 version 22.0 documentation
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# goto

Perl functions A-Z | Perl functions by category | The 'perlfunc' manpage

- goto LABEL

- goto EXPR
- goto &NAME

  The `goto LABEL` form finds the statement labeled with LABEL and resumes execution there. It can't be used to get out of a block or subroutine given to `sort`. It can be used to go almost anywhere else within the dynamic scope, including out of subroutines, but it's usually better to use some other construct such as `last` or `die`. The author of Perl has never felt the need to use this form of `goto` (in Perl, that is; C is another matter). (The difference is that C does not offer named loops combined with loop control. Perl does, and this replaces most structured uses of `goto` in other languages.)

  The `goto EXPR` form expects to evaluate `EXPR` to a code reference or a label name. If it evaluates to a code reference, it will be handled like `goto &NAME` , below. This is especially useful for implementing tail recursion via `goto __SUB__` .

  If the expression evaluates to a label name, its scope will be resolved dynamically. This allows for computed `goto`s per FORTRAN, but isn't necessarily recommended if you're optimizing for maintainability:

          goto ("FOO", "BAR", "GLARCH")[$i];

  As shown in this example, `goto EXPR` is exempt from the "looks like a function" rule. A pair of parentheses following it does not (necessarily) delimit its argument. `goto("NE")."XT"` is equivalent to `goto NEXT` . Also, unlike most named operators, this has the same precedence as assignment.

  Use of `goto LABEL` or `goto EXPR` to jump into a construct is deprecated and will issue a warning. Even then, it may not be used to go into any construct that requires initialization, such as a subroutine or a `foreach` loop. It also can't be used to go into a construct that is optimized away.

  The `goto &NAME` form is quite different from the other forms of `goto`. In fact, it isn't a goto in the normal sense at all, and doesn't have the stigma associated with other gotos. Instead, it exits the current subroutine (losing any changes set by local()) and immediately calls in its place the named subroutine using the current value of @_. This is used by `AUTOLOAD` subroutines that wish to load another subroutine and then pretend that the other subroutine had been called in the first place (except that any modifications to `@_` in the current subroutine are propagated to the other subroutine.) After the `goto`, not even `caller` will be able to tell that this routine was called first.

  NAME needn't be the name of a subroutine; it can be a scalar variable containing a code reference or a block that evaluates to a code reference.