Why don't self-closing script elements work?
<script> tags should be explicitly closed using </script>. Self-closing <script /> is deemed invalid in HTML, leading to script failure. Opt for:
HTML allows void elements like <img> or <br> to be self-closed, but <script> tags mandate explicit closing for successful script execution. Precision in handling tags plays a pivotal role here.
Decoding HTML and XHTML: A technical overview
Foundations: Understanding the SGML legacy
HTML and XHTML are born from SGML (Standard Generalized Markup Language). According to SGML, script elements encompass PCDATA (Parsed Character Data). This strongly suggests that a <script> tag requires an opening and closing pair, encapsulating script content. Since self-closing isn't recognized here, any browser following these rules won't interpret <script /> as expected.
XHTML vs HTML: How MIME types matter
For XHTML document which is XML-based, self-closing syntax may seem valid. However, most web hosts serve XHTML as text/html due to historical browser compatibility issues, mainly with Internet Explorer. This causes the browser to parse under HTML rules, leading to unexpected consequences with self-closing <script> tags.
HTML5's stance on self-closing syntax
HTML5 allows self-closing syntax exclusively for specific "void" elements (like <br>, <hr>) and "foreign" elements. <script> isn't a void element and necessitates a closing tag to maintain consistent rendering and backward compatibility across a variety of browsers.
The practical side: Best practices and implications
Serving XHTML content: An art and a science
For XHTML content, use 'application/xhtml+xml' MIME type for web hosts to parse your document correctly consistently. However, bear in mind that serving XHTML as 'text/html' could lead to inconsistencies as HTML parsing rules will apply.
A walk through history: The story of browser parsing models
Understanding the historical origins of browser parsing models gains significance while dealing with these issues. The way a browser handles <script> tags is guided by its roots in SGML—significant insight when approaching current web development challenges.
Cross-browser compatibility: Be ready for a wild ride
Browser compatibility bugs are a reality one should be ready for. Sticking with opening and closing tags ensures consistent interpretation by browser parsers. Testing your content extensively across different browsers is a critical step - the cross-browser, cross-platform, *cross-everything* nature of web development demands it.
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