{"id":6494,"date":"2020-01-25T21:42:06","date_gmt":"2020-01-25T20:42:06","guid":{"rendered":"https:\/\/monodes.com\/predaelli\/?p=6494"},"modified":"2020-01-25T21:42:06","modified_gmt":"2020-01-25T20:42:06","slug":"a-quick-dive-into-pythons-__slots__-noteworthy-the-journal-blog","status":"publish","type":"post","link":"https:\/\/monodes.com\/predaelli\/2020\/01\/25\/a-quick-dive-into-pythons-__slots__-noteworthy-the-journal-blog\/","title":{"rendered":"A quick dive into Python\u2019s \u201c__slots__\u201d – Noteworthy – The Journal Blog"},"content":{"rendered":"

A quick dive into Python\u2019s \u201cslots<\/strong>\u201d – Noteworthy – The Journal Blog<\/a><\/em><\/p>\n

Or how to try mimik a strongly typed language in a weakly typed one or something like this….<\/p>\n

<\/p>\n

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A quick dive into Python\u2019s \u201c__slots__\u201d<\/h1>\n<\/div>\n
\n
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\"Stephen<\/a><\/div>\n
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Stephen Jayakar<\/a><\/span><\/p>\n
<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n
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Nov 10, 2018<\/a> \u00b7 6 min read<\/div>\n<\/div>\n<\/div>\n

or my first Medium article, we\u2019re going to go into a quick and easy way to speed up your Python code (and pass those pesky HackerRank tests where you\u2019re just a bit short on time!), as well as some of the technical implementation details for the curious.<\/p>\n

__slots__<\/code> is an attribute you can add to a Python class when defining it. You define slots with the possible attributes that an instance of an object can possess. Here\u2019s how you use __slots__<\/code>:<\/p>\n\n\n\n
class<\/span> WithSlots<\/span>:<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n\n\n\n
__slots__<\/span> =<\/span> (‘x’<\/span>, ‘y’<\/span>)<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n\n\n\n
<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n\n\n\n
def<\/span> __init__<\/span>(self<\/span>, x<\/span>, y<\/span>):<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

self<\/span>.x<\/span>, self<\/span>.y<\/span> =<\/span> x<\/span>, y<\/span><\/p>\n

For instances of this class, you can use self.x<\/code> and self.y<\/code> in the same ways as a normal class instance. However, one key difference between this and instancing from a normal class is that you cannot add or remove<\/em> attributes from this class\u2019 instances. Say the instance was called w<\/code>: you couldn\u2019t write w.z = 2<\/code> without causing an error.<\/p>\n

The biggest higher-level reasons to use __slots__<\/code> are 1) faster attribute getting and setting<\/strong> due to data structure optimization and 2) reduced memory usage<\/strong> for class instances. Some reasons you wouldn\u2019t want to use it is if your class has attributes that change during run-time (dynamic attributes) or if there\u2019s a complicated object inheritance tree.<\/p>\n<\/blockquote>\n","protected":false},"excerpt":{"rendered":"

A quick dive into Python\u2019s \u201cslots\u201d – Noteworthy – The Journal Blog Or how to try mimik a strongly typed language in a weakly typed one or something like this….<\/p>\n

Read more →<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"inline_featured_image":false,"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"activitypub_content_warning":"","activitypub_content_visibility":"","activitypub_max_image_attachments":4,"activitypub_interaction_policy_quote":"anyone","activitypub_status":"","footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[72,113],"tags":[],"class_list":["post-6494","post","type-post","status-publish","format-standard","hentry","category-documentations","category-python"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p6daft-1GK","jetpack-related-posts":[{"id":9039,"url":"https:\/\/monodes.com\/predaelli\/2022\/01\/01\/deciphering-glyph-the-one-python-library-everyone-needs\/","url_meta":{"origin":6494,"position":0},"title":"Deciphering Glyph :: The One Python Library Everyone Needs","author":"Paolo Redaelli","date":"2022-01-01","format":"link","excerpt":"Use attrs. 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