CSS大解剖 1日目: 「仕様書」
本稿は、2024年2月頃に書き溜めていたシリーズです。最後まで温存させるのが勿体ないので、未完成ですがそのまま公開します(公開日: 2025/9/21)。そのため、内容の重複や記述方針の不一致があるかもしれませんが、ご理解ください。 CSSの仕様を理解するために、1日ごとにテーマを決めて説明する企画1日目です。今日のテーマは「仕様書」です。 仕様書 CSSはWebの標準化団体であるW3Cによって標準化され、各ブラウザベンダによって実装されている規格です。 標準化して挙動を仕様書として書き起こすことによって、Webブラウザ間の相互運用性が高まり、Web開発者も互換性の高い記述を心掛けてCSSを書くことができるようになります。 とはいえ、仕様書と実装の関係は必ずしも一方向的ではありません。「仕様書に記載される → 実装される」というシンプルな順番であるとは限らないのです。実装されたものにあわせ
Wasm 3.0 Completed - WebAssembly
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Make <img> src attribute optional if srcset is present · Issue #9181 · whatwg/html
https://html.spec.whatwg.org/multipage/embedded-content.html#the-img-element currently requires: The src attribute must be present, and must contain a valid non-empty URL potentially surrounded by spaces referencing a non-interactive, optionally animated, image resource that is neither paged nor scripted. and The srcset attribute may also be present, and is a srcset attribute. In other words, a va
RFC 1918: Address Allocation for Private Internets
[RFC Home] [TEXT|PDF|HTML] [Tracker] [IPR] [Errata] [Info page] BEST CURRENT PRACTICE Updated by: 6761 Errata ExistNetwork Working Group Y. Rekhter Request for Comments: 1918 Cisco Systems Obsoletes: 1627, 1597 B. Moskowitz BCP: 5 Chrysler Corp. Category: Best Current Practice D. Karrenberg RIPE NCC G. J. de Groot RIPE NCC E. Lear Silicon Graphics, Inc. February 1996 Address Allocation for Private
Introduce `moveBefore()` state-preserving atomic move API by domfarolino · Pull Request #1307 · whatwg/dom
This PR introduces a new DOM API on the ParentNode mixin: moveBefore(). It mirrors insertBefore() in shape, but defers to a new DOM manipulation primitive that this PR adds in service of this new API: the "move" primitive. The move primitive contains some of the DOM tree bookkeeping steps from the remove primitive, as well as the insert primitive, and does three more interesting things: Calls the
Standard Schema
Standard SchemaFor entities that validate and transform data The Standard Schema project is a set of interfaces that standardize the provision and consumption of shared functionality in the TypeScript ecosystem. Its goal is to allow tools to accept a single input that includes all the types and capabilities they need— no library-specific adapters, no extra dependencies. The result is an ecosystem
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Let’s Define CSS 4 · Issue #4770 · w3c/csswg-drafts
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Consensus in Internet Standards
Hi, I’m Mark Nottingham. I write about the Web, protocol design, HTTP, Internet governance, and more. This is a personal blog, it does not represent anyone else. Find out more. Comments? Let's talk on Mastodon. @mnot@techpolicy.social other Standards posts The Nature of Internet Standards (series) RFC 9518 - What Can Internet Standards Do About Centralisation? Tuesday, 19 December 2023 RFC 8890 -
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Release ES2026 Candidate March 31st 2026 · tc39/ecma262
Merkle Integrity Content Encoding
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