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    for an outer join, you would get
    { 'name': 'something', 'type': 'foo', 'typeName': 'foo', 'hasSetting': 1}
    { 'name': 'blarg', 'type': 'hip'}
    { 'typeName': 'bar', 'hasSetting': 0 }
 
    for a left join, you would get
    { 'name': 'something', 'type': 'foo', 'typeName': 'foo', 'hasSetting': 1}
    { 'typeName': 'bar', 'hasSetting': 0 }
 
    for a right join, you would get
    { 'name': 'something', 'type': 'foo', 'typeName': 'foo', 'hasSetting': 1}
    { 'name': 'blarg', 'type': 'hip'}
 
 Accumulate Right:
    Accumulate all input records with the same key onto each db record matching
    that key. This means that a db record can have multiple input records merged
    into it. If no operation is provided, any fields in second or later records
    will be lost due to them being discarded. This option is most useful with a
    user defined operation to handle collisions. For example, one could provide
    an operation to add fields together:
 
    recs-join --left --operation '
      foreach $k (keys %$i) {
        if (exists($d->{$k})) {
          if ($k =~ /^value/) {$d->{$k} = $d->{$k} + $i->{$k};}
        } else {
          $d->{$k} = $i->{$k};
        }
      }' --accumulate-right name name dbfile inputfile
 
 Help from: --help-keyspecs:
   KEY SPECS
    A key spec is short way of specifying a field with prefixes or regular
    expressions, it may also be nested into hashes and arrays. Use a '/' to nest
    into a hash and a '#NUM' to index into an array (i.e. #2)
 
    An example is in order, take a record like this:
 
      {"biz":["a","b","c"],"foo":{"bar 1":1},"zap":"blah1"}
      {"biz":["a","b","c"],"foo":{"bar 1":2},"zap":"blah2"}
      {"biz":["a","b","c"],"foo":{"bar 1":3},"zap":"blah3"}
 
    In this case a key spec of 'foo/bar 1' would have the values 1,2, and 3 in
    the respective records.
 
    Similarly, 'biz/#0' would have the value of 'a' for all 3 records
 
    You can also prefix key specs with '@' to engage the fuzzy matching logic
 
    Fuzzy matching works like this in order, first key to match wins
      1. Exact match ( eq )
      2. Prefix match ( m/^/ )
      3. Match anywehre in the key (m//)
 
    So, in the above example '@b/#2', the 'b' portion would expand to 'biz' and 2
    would be the index into the array, so all records would have the value of 'c'
 
    Simiarly, @f/b would have values 1, 2, and 3
 
    You can escape / with a \. For example, if you have a record:
    {"foo/bar":2}
 
    You can address that key with foo\/bar
 
 Help from: --help-snippet:
    CODE SNIPPETS:
     Recs code snippets are perl code, with one exception. There a couple of
     variables predefined for you, and one piece of special syntax to assist in
     modifying hashes.
 
 Special Variables:
     $r - the current record object. This may be used exactly like a hash, or you
     can use some of the special record functions, see App::RecordStream::Record
     for more information
 
     $line - This is the number of records run through the code snippet, starting
     at 1. For most scripts this corresponds to the line number of the input to
     the script.
 
     $filename - The filename of the originating record. Note: This is only
     useful if you're passing filenames directly to the recs script, piping
     from other recs scripts or from cat, for instance, will not have a
     useful filename.
 
 Special Syntax
     Use {{search_string}} to look for a string in the keys of a record, use /
     to nest keys. You can nest into arrays by using an index. If you are
     vivifying arrays (if the array doesn't exist, prefix your key with # so
     that an array rather than a hash will be created to put a / in your key,
     escape it twice, i.e. \/
 
     This is exactly the same as a key spec that is always prefaced with a @, see
     'man recs' for more info on key specs
 
     For example: A record that looks like:
     { "foo" : { "bar 1" : 1 }, "zoo" : 2}
     Could be accessed like this:
 
     # value of zoo  # value of $r->{foo}->{bar 1}: (comma separate nested keys)
     {{zoo}}         {{foo/ar 1}}
 
     # Even assign to values (set the foo key to the value 1)
     {{foo}} = 1
 
     # And auto, vivify
     {{new_key/array_key/#0}} = 3 # creates an array within a hash within a hash
 
     # Index into an array
     {{array_key/#3}} # The value of index 3 of the array ref under the
     'array_key' hash key.
 
     This matching is a fuzzy keyspec matching, see --help-keyspecs for
     more details.
 

=head1 SEE ALSO

=over

=item * See L<App::RecordStream> for an overview of the scripts and the system

=item * Run C<recs examples> or see L<App::RecordStream::Manual::Examples> for a set of simple recs examples

=item * Run C<recs story> or see L<App::RecordStream::Manual::Story> for a humorous introduction to RecordStream

=item * Every command has a C<--help> mode available to print out usage and
examples for the particular command, just like the output above.

=back