My personal feedback...

Never place two statements on the same line unless they are somehow related or part of the same logic process. Always start your elsif or else block on a new line. unless the last elsif block contains a very short line and the next else {} block also contains a very short line. In that case, it's ok. For example: elsif ($Color & 255) { $RGB++; } else { $GRAY++; }

Doing that breaks readibility flow.

Use CamelCase whenever possible, for more important variables, use all uppercase letters.

That breaks decades of the de-facto Perl standardized naming scheme of snake_case.

Avoid using constants as much as possible. But if you must, use all caps and very short names for constants (4-5 letters).

Use constants whenever they are deemed necessary, instead of global variables, and don't limit the name length. The variable name should be as long as needed so that it conveys what the variable's purpose is. Here are two examples:

use constant {
 
    DEFAULT_QUEUE       => 0x03,  # bits 1-0 (0-3)
    MAX_QUEUE           => 0x03,
 
    DEFAULT_POLARITY    => 0x00,  # bit  3
    MAX_POLARITY        => 0x08,
 
    DEFAULT_RATE        => 0x00,  # bits 7-5
    MAX_RATE            => 0xE0,
 
    DEFAULT_MODE        => 0x100, # bit  8
    MAX_MODE            => 0x100,
 
    DEFAULT_GAIN        => 0x200, # bits 11-9
    MAX_GAIN            => 0xE00,
 
    DEFAULT_CHANNEL     => 0x4000, # bits 14-12
    MAX_CHANNEL         => 0x7000,
};

[download]
use constant {
    DEBUG_CACHE                 => $ENV{DEBUG_TESLA_API_CACHE},
    API_CACHE_PERSIST           => 0,
    API_CACHE_TIMEOUT_SECONDS   => 2,
    API_TIMEOUT_RETRIES         => 3,
    AUTH_CACHE_FILE             => "$home_dir/tesla_auth_cache.json",
    ENDPOINTS_FILE              => $ENV{TESLA_API_ENDPOINTS_FILE} // d
+ist_file('Tesla-API', 'endpoints.json'),
    OPTION_CODES_FILE           => $ENV{TESLA_API_OPTIONCODES_FILE} //
+ dist_file('Tesla-API', 'option_codes.json'),
    TOKEN_EXPIRY_WINDOW         => 5,
    URL_API                     => 'https://owner-api.teslamotors.com/
+',
    URL_ENDPOINTS               => 'https://raw.githubusercontent.com/
+tdorssers/TeslaPy/master/teslapy/endpoints.json',
    URL_OPTION_CODES            => 'https://raw.githubusercontent.com/
+tdorssers/TeslaPy/master/teslapy/option_codes.json',
    URL_AUTH                    => 'https://auth.tesla.com/oauth2/v3/a
+uthorize',
    URL_TOKEN                   => 'https://auth.tesla.com/oauth2/v3/t
+oken',
    USERAGENT_STRING            => 'Mozilla/5.0 (Macintosh; Intel Mac 
+OS X 10.15; rv:98.0) Gecko/20100101 Firefox/98.0',
    USERAGENT_TIMEOUT           => 180,
};

[download]
Always use warnings and strict. Adopt a policy of zero tolerance for warnings and errors.

That should be rule number one. Rule number two (IMHO) should be write tests as you write code. Let the test code help you dictate the interface.

Lines should not exceed 70 characters unless absolutely necessary.

This is actually 80, because years ago that was the width of a terminal. This isn't really necessary any longer (but I do still for the vast majority of the time stick with it).

I don't like to use TABS. I always use two spaces to indent code.

Much more common is four-space tabs.

In reply to Re^2: 20 most important Perl Best Practices by stevieb
in thread 20 most important Perl Best Practices by greengaroo

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.