{"id":286813,"date":"2026-10-03T10:03:54","date_gmt":"2026-10-03T10:03:54","guid":{"rendered":"https:\/\/ushopwell.com\/ublog\/var-vs-let-vs-const-and-why-you-should-almost-never-use-var-again\/"},"modified":"2026-10-03T10:03:54","modified_gmt":"2026-10-03T10:03:54","slug":"var-vs-let-vs-const-and-why-you-should-almost-never-use-var-again","status":"publish","type":"post","link":"https:\/\/ushopwell.com\/ublog\/var-vs-let-vs-const-and-why-you-should-almost-never-use-var-again\/","title":{"rendered":"var vs let vs const, and why you should almost never use var again."},"content":{"rendered":"<div class=\"youtubomatic-video-container\"><iframe loading=\"lazy\" width=\"580\" height=\"380\" src=\"https:\/\/www.youtube.com\/embed\/g4bROzRE2ec?autoplay=1&#038;controls=1&#038;hl=en\" frameborder=\"0\" allowfullscreen><\/iframe><\/div>\n<p>var vs let vs const, and why you should almost never use var again.<\/p>\n<p>var is function scoped and can be redeclared. It also gets hoisted, which means you can reference it before you declared it and get undefined instead of an error. That is the source of some genuinely confusing bugs.<br \/>\nlet is block scoped. It exists only inside the braces it was declared in, and it can be reassigned.<br \/>\nconst is block scoped and cannot be reassigned.<\/p>\n<p>One detail interviewers like: const does not make an object immutable. You cannot point the name at something new, but you can still change the properties inside it. Use readonly or Object.freeze if you need more.<\/p>\n<p>Practical rule: use const by default, let when the value genuinely changes, var never.<\/p>\n<p>Save this \u2705<\/p>\n<p>#typescript #javascript #playwright #sdet #interviewpreparation #testautomation<\/p>\n","protected":false},"excerpt":{"rendered":"<p>var vs let vs const, and why you should almost never use var again. var is function scoped and can be redeclared. It also gets hoisted, which means you can reference it before you declared it and get undefined instead of an error. That is the source of some genuinely confusing bugs. let is block scoped. It exists only inside the braces it was declared in, and it can be&#8230;<\/p>\n","protected":false},"author":1,"featured_media":286814,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","tve_updated_post":"","tve_custom_css":"","tve_user_custom_css":"","tve_globals":{},"tcb2_ready":0,"tcb_editor_enabled":0,"tve_landing_page":"","_tve_header":"","_tve_footer":""},"categories":[1],"tags":[],"class_list":["post-286813","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-uncategorized"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v28.7 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>var vs let vs const, and why you should almost never use var again. - UshopWell.com<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/ushopwell.com\/ublog\/var-vs-let-vs-const-and-why-you-should-almost-never-use-var-again\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"var vs let vs const, and why you should almost never use var again. - UshopWell.com\" \/>\n<meta property=\"og:description\" content=\"var vs let vs const, and why you should almost never use var again. var is function scoped and can be redeclared. 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