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README.md

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+# HTML templating language
+A common task with HTML is creating 'templates', or reusable components
+that are stitched together to form a complete document. Front end frameworks 
+typically achieve this through scripting on the client. I prefer instead to 
+generate static HTML files on the server. To this end, I wrote my own templating
+engine. It parses HTML source and template files, and produces output files which
+are minified and with CSS and JavaScript inlined. Additional post processing can
+be performed, like syntax highlighting for code blocks.
+
+Existing Rust for parsing HTML use recursive descent, outputting a tree
+data structure. I prefer flat data structures and linear algorithms, and so
+I wrote my own parser. 
+
+```rust
+// My lexeme type (fields omitted)
+pub enum HtmlElement {
+  DocType,
+  Comment   (...),
+  OpenTag   {...},
+  CloseTag  {...},
+  Text      (...),
+  Script    {...},
+  Style     {...},
+  Directive {...},
+}
+```
+Lexemes are stored in a flat array. Tags are consumed by taking a slice of
+the array from the opening tag until the closing tag. Expanding a template
+is done by simply copying its contents into the array. Directives, prefixed
+with an @ can pass properties and child nodes to a template.
+```html
+<!-- This is a template definition -->
+<Demo>
+  <h1 id=@prop_name>
+    <@children>
+  </h1>
+</Demo>
+
+<!-- This is a template instantiation -->
+<Demo prop_name="something">
+  <i> Hello World! </i>
+</Demo>
+
+<!-- This is how the template gets expanded -->
+<h1 id="something"/>
+  <i> Hello World! </i>
+</h1>
+```
+The templating engine is free-standing by default, but optionally integrates
+with Tree Sitter to highlight and format code blocks. To do this I use
+the [inkjet](https://crates.io/crates/inkjet) and 
+[v_htmlescape](https://crates.io/crates/v_htmlescape) crates.
+