You are viewing the version of this documentation from Perl 5.31.4. This is a development release of Perl.
$PREMATCH
$`

The string preceding whatever was matched by the last successful pattern match, not counting any matches hidden within a BLOCK or eval enclosed by the current BLOCK.

See "Performance issues" above for the serious performance implications of using this variable (even once) in your code.

This variable is read-only and dynamically-scoped.

Mnemonic: ` often precedes a quoted string.