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# pos

Perl 5 version 18.2 documentation
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# pos

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

- pos SCALAR

- pos

  Returns the offset of where the last `m//g` search left off for the variable in question (`$_` is used when the variable is not specified). Note that 0 is a valid match offset. `undef` indicates that the search position is reset (usually due to match failure, but can also be because no match has yet been run on the scalar).

  `pos` directly accesses the location used by the regexp engine to store the offset, so assigning to `pos` will change that offset, and so will also influence the `\G` zero-width assertion in regular expressions. Both of these effects take place for the next match, so you can't affect the position with `pos` during the current match, such as in `(?{pos() = 5})` or `s//pos() = 5/e` .

  Setting `pos` also resets the matched with zero-length flag, described under Repeated Patterns Matching a Zero-length Substring in perlre.

  Because a failed `m//gc` match doesn't reset the offset, the return from `pos` won't change either in this case. See perlre and perlop.