# Consume matching text, if found next:
sub eat {
    my( $re,            # Regex or string to match against next part of doc.
        $keep_ws,       # Don't skip over whitespace first?
        $sv,            # Append matched text to referenced scalar (if any).
        $to_end,        # Allow match to hit end of $Buf?
        $peek,          # Keep pos() unchanged?
    ) = @_;
    $Buf =~ /\G\s+/gc
        if  ! $keep_ws;
    my $start = pos( $Buf );
    $re = _compile( $re );  # Prepends \G also
    do {
        return 0
            if  $Buf !~ /$re/gc;
    } while( ! $to_end && _hit_end(\$start) );
    $$sv .= substr( $Buf, $start, pos($Buf)-$start )
        if  $sv;
    pos($Buf) = $start
        if  $peek;
    return 1;
}

##</code><code>##

# Consume matching text, if found next:
sub eat {
    my( $re,            # Regex or string to match against next part of doc.
        $keep_ws,       # Don't skip over whitespace first?
        $sv,            # Append matched text to referenced scalar (if any).
        $to_end,        # Allow match to hit end of $Buf?
        $peek,          # Keep pos() unchanged?
    ) = @_;
    0   while   ! $keep_ws
            &&  eat( '\s+', 1, '', 1 );
    my $start = pos( $Buf );
    _hit_end( \$start );
    $re = _compile( $re );  # Prepends \G also
    do {
        return 0
            if  $Buf !~ /$re/gc;
    } while( ! $to_end && _hit_end(\$start) );
    $$sv .= substr( $Buf, $start, pos($Buf)-$start )
        if  $sv;
    pos($Buf) = $start
        if  $peek;
    return 1;
}