How to filter any part of description or option from manpage

I wrote a small script to do this called he, e.g. he apt-get autoclean.

The basic strategy is: search for the word (e.g. autoclean) as the first word on a line, then print until the next blank line.

You can get something similar using basic sed, e.g.

man apt-get | sed -ne '/^  *autoclean/,/^$/p'

You can find the script on my github page (linked above) and I am including its source here:

#!/bin/sh
# he - print brief help about a single option or command
# Mikel Ward <[email protected]>
# Example Usage:
# he bash continue
# he rsync -v
scriptname=he
usage()
{
    cat <<EOF 1>&2
Usage: $scriptname <command> [<option|section>]
Example:
$scriptname bash getopts (shows documentation for bash getopts)
$scriptname ssh -v (shows documentation for ssh -v flag)
$scriptname select (shows SYNOPSIS for select(2))
$scriptname 'open(2)' (shows SYNOPSIS for open(2))
EOF
}
if test $# -lt 1; then
    usage
    exit 2
fi
manpage="$1"
# show the SYNOPSIS section if no section or option was given
option="${2:-SYNOPSIS}"
# handle manpage(number)
case $manpage in *\(*\))
    page=${manpage%\(*\)}
    section=${manpage#$page}
    section=${section#\(}
    section=${section%\)}
    manpage=$page
    ;;
esac
man ${section:+-s $section} "$manpage" | perl -n -e '
BEGIN {
    $option = "'$option'";
    $inside = 0;
    }
    if (!$inside) {
    if (/^(\s*)\Q$option\E\b/p) {
        # start of this option
        $spaces = $1;
        $inside = 1;
        print;
    }
}
else {
    if (/^$spaces\S/) {
    # start of next option;
    exit;
    }
    elsif (/^\S/) {
        # start of next section
        exit;
    }
    else {
        print;
    }
}
'