comment on

> I found that if I got the data structures correct, the code usually flowed. If not, things got messy fast.

This reminds me of some famous quotes from Fred Brooks, Rob Pike, Eric S. Raymond, and Linus Torvalds:

The programmer at wit's end for lack of space can often do best by disentangling himself from his code, rearing back, and contemplating his data. Representation is the essence of programming.

-- from The Mythical Man Month by Fred Brooks

Data dominates. If you've chosen the right data structures and organized things well, the algorithms will almost always be self-evident. Data structures, not algorithms, are central to programming.

-- Rob Pike

Show me your code and conceal your data structures, and I shall continue to be mystified. Show me your data structures, and I won't usually need your code; it'll be obvious.

-- Eric S. Raymond

I will, in fact, claim that the difference between a bad programmer and a good one is whether he considers his code or his data structures more important. Bad programmers worry about the code. Good programmers worry about data structures and their relationships.

-- Linus Torvalds

Perl Data Structure References

perldsc - Perl Data Structures Cookbook
perlreftut - Perl References Tutorial
perlref - Perl References
perldata - Perl Data Types
perlvar - Perl predefined variables
perllol - Arrays of arrays in Perl
perlobj - Perl objects
Storable - Persistence for Perl Data Structures

Tie::Hash - base class definitions for tied hashes

YAML - YAML Ain't Markup Language
JSON - JSON (JavaScript Object Notation) encoder/decoder
JSON::MaybeXS - Use Cpanel::JSON::XS with a fallback to JSON::XS and JSON::PP
TOML - Parser for Tom's Obvious, Minimal Language
TOML Spec (github)

Sereal - Fast, compact, powerful binary (de-)serialization
SerealX::Store - Sereal based persistence for Perl data structures
Config::Any - Load configuration from different file formats, transparently
Config::Tiny - Read/Write .ini style files with as little code as possible
Config::INI - simple .ini-file format

SQLite (wikipedia)
DBI and one of the many DBD::* modules
DBD::SQLite

Data::Dumper - stringified perl data structures, suitable for both printing and eval
Data::Dump - Pretty printing of data structures

Re: access object values by kcott (2023) - displaying/debugging Perl data structures and references
Re: Why can't some of my modules do log output to a file? by haukex (2022) - example of turning on Data::Dumper's Useqq option

Memory efficient way to deal with really large arrays? by sectokia (2020)
Re: Memory efficient way to deal with really large arrays? by Tux (2020) - Perl benchmarked faster than every database tried (SQLite, Pg, mysql, MariaDB)

Re^2: A good way to input data into a script w/o an SQL database by ObiPanda (2023) - asking about code vs data in a script
How can I send a "transposed slice" of an array of hashes and by extension an array of arrays, or hash of hashes to a subroutine by ObiPanda (2023) - ... continued

using TIEHASH as wrapper/proxy, while avoiding recursion and warnings by LanX (2024) - using Tie::Hash as a temporary wrapper

Modules as configuration files by Discipulus (2015)
Preserve the order in JSON by user786 (2015)

Perl 4 multidimensional array emulation:

perlvar - if you refer to a hash element as $foo{$a,$b,$c} it really means $foo{join($;, $a, $b, $c)} ... where $; is the subscript separator for multidimensional array emulation aka $SUBSUP (default \034), borrowed from awk

feature - note that Perl 5.34+ allows you to disable this old Perl 4 multidimensional array emulation via the 'multidimensional' feature
perl 5.36 delta - ... and that use v5.36; disables multidimensional array emulation
Whats new in Perl (youtube) by Ricardo Signes (TPC 2021) uses What is this madness? to describe this unfortunate multidimensional mis-feature :-)

Multidimensional arrays by Bod (2023) - asking for advice on which Perl data structure to use
CGI::Carp sometimes fails by Bod (2024) - it appears Bod is still using multidimensional array emulation

Storable for user preferences by Bod (2023)
Re: Storable for user preferences by afoken (2023)

See Also

Build and Test Automation References:

Perl CPAN test metadata by me (2010)
Data-driven Programming: fun with Perl, JSON, YAML, XML... by me (2015)

Updated: Many extra references added long after the original reply was made.

In reply to Re^3: How does one learn perl programming efficiently - if they do not come from computer science background? (Data Structure References) by eyepopslikeamosquito
in thread How does one learn perl programming efficiently - if they do not come from computer science background? by ktsirig

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