--- title: [RFC] [Discussion] Bound-Erased Generic Types | daily.dev description: A PHP internals mailing list discussion about a proposed RFC for bound-erased generic types in PHP. The thread covers a working implementation of reified... canonical: https://daily.dev/posts/rfc-discussion-bound-erased-generic-types-02zyytqdb twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: [RFC] [Discussion] Bound-Erased Generic Types | daily.dev og:description: A PHP internals mailing list discussion about a proposed RFC for bound-erased generic types in PHP. The thread covers a working implementation of reified... og:url: https://daily.dev/posts/rfc-discussion-bound-erased-generic-types-02zyytqdb og:image: https://api.daily.dev/og/posts/02ZyyTQdb.png og:image:alt: [RFC] [Discussion] Bound-Erased Generic Types og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # [RFC] [Discussion] Bound-Erased Generic Types **[externals.io](https://daily.dev/sources/externals)** · 9 min read · 0 upvotes · 0 comments ## Summary A PHP internals mailing list discussion about a proposed RFC for bound-erased generic types in PHP. The thread covers a working implementation of reified generics built on top of the bound-erased branch, comparing the two approaches. Key points include: reified generics use class monomorphization at runtime, performance overhead is roughly 1.3-1.5x vs no type checking (comparable to manual type checks), erased generics have a critical footgun with exception catching where generic catch blocks silently fail, and reified generics support limited type inference. Rob Landers argues strongly that erased generics are insufficient because they don't enforce correctness, break pattern matching, and mislead developers about code behavior — advocating for checked/reified generics instead. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Similar posts on daily.dev - [\[RFC\] \[Discussion\] Bound-Erased Generic Types](https://daily.dev/posts/rfc-discussion-bound-erased-generic-types-9qvm5mvun) · externals.io · 0 upvotes · 0 comments - [\[RFC\] \[Discussion\] Bound-Erased Generic Types](https://daily.dev/posts/rfc-discussion-bound-erased-generic-types-lczfjcxhx) · externals.io · 0 upvotes · 0 comments - [\[RFC\] \[Discussion\] Bound-Erased Generic Types](https://daily.dev/posts/rfc-discussion-bound-erased-generic-types-ze8fx3ymf) · externals.io · 0 upvotes · 0 comments - [\[RFC\] \[Discussion\] Bound-Erased Generic Types](https://daily.dev/posts/rfc-discussion-bound-erased-generic-types-su8puw4vm) · externals.io · 0 upvotes · 0 comments - [\[RFC\] \[Discussion\] Bound-Erased Generic Types](https://daily.dev/posts/rfc-discussion-bound-erased-generic-types-9glaigzvf) · externals.io · 0 upvotes · 0 comments --- Tags: [#php](https://daily.dev/tags/php) [View this post on daily.dev](https://daily.dev/posts/rfc-discussion-bound-erased-generic-types-02zyytqdb) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"[RFC] [Discussion] Bound-Erased Generic Types","url":"https://daily.dev/posts/rfc-discussion-bound-erased-generic-types-02zyytqdb","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/rfc-discussion-bound-erased-generic-types-02zyytqdb"},"datePublished":"2026-06-08T19:12:07.153Z","dateModified":"2026-06-08T19:24:16.264Z","description":"A PHP internals mailing list discussion about a proposed RFC for bound-erased generic types in PHP. 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