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    "find me!"

A less specific query on the same data structure:

    %my_cool_hash->{'a'}

Will return that branch of the tree:

    ["blub", { needle => "find me!", some_other_key => "blorb" }]

Other syntactic examples:

    $hash_ref->{'a'}->[0]->[3]->{'blorg'}
    @array->[0]->{'foo'}
    $array_ref->[0]->{'foo'}
    $scalar

#### QUERY SYNTAX ALTNERATIVES

The query syntax attempts to provide a reasonable amount of power
for navigating Perl data structures without risking the stability of the system
under inspection.

In other words, while `eval '$my_cool_hash{a}->[1]->{needle}'` would
be a much more powerful solution to the problem of navigating Perl data
structures, it opens up all the cans of worms at once.

The current syntax might be a little bit "uncanny valley" in that it looks like
Perl, but is not Perl. It is Perl-ish. It also might be too complex, since it
allows fancy things like nested resolution:

    $foo->{$bar}

Or even:

    %my_hash->{$some_arrayref->[$some_scalar->{'key'}]}->{'needle'}

Ouch. In practice I hope and expect that the majority of queries will be
simple scalars, or maybe one or two chained hashkey/array index lookups.

I'm open to exploring other syntax in this area as long as it is aligned with
the following goals:

- Simple query model

    As a debugging tool, you have enough on your brain just debugging your system.
    Second-guessing your query syntax when you get unexpected results is a major
    distraction and leads to loss of trust in the tool (I'm looking at you,
    ElasticSearch).

- O(1), not O(n) (or worse)

    I'd like to avoid globs or matching syntax that might end up iterating over
    unbounded chunks of a data structure. Traversing a small, fixed number of keys
    in 'parallel' sounds like a sane extension, but anything which requires
    iterating over the entire set of hash keys or array indicies is likely to
    surprise when debugging systems with unexpectedly large data structures.

# SEE ALSO

- [PadWalker](https://metacpan.org/pod/PadWalker)
- [Devel::Probe](https://metacpan.org/pod/Devel::Probe)