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# redo

Perl 5 version 16.0 documentation
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# redo

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

- redo LABEL

- redo

  The `redo` command restarts the loop block without evaluating the conditional again. The `continue` block, if any, is not executed. If the LABEL is omitted, the command refers to the innermost enclosing loop. Programs that want to lie to themselves about what was just input normally use this command:

          # a simpleminded Pascal comment stripper    # (warning: assumes no { or } in strings)    LINE: while (<STDIN>) {        while (s|({.*}.*){.*}|$1 |) {}        s|{.*}| |;        if (s|{.*| |) {            $front = $_;            while (<STDIN>) {                if (/}/) {  # end of comment?                    s|^|$front\{|;                    redo LINE;                }            }        }        print;    }

  `redo` cannot be used to retry a block that returns a value such as `eval {}` , `sub {}` , or `do {}` , and should not be used to exit a grep() or map() operation.

  Note that a block by itself is semantically identical to a loop that executes once. Thus `redo` inside such a block will effectively turn it into a looping construct.

  See also continue for an illustration of how `last`, `next`, and `redo` work.