Will Anderson
a54b2bebf9
- el_runtime.js: add 19 dom_* builtins (browser-only, throw in Node), window_set/window_get for exposing El functions to the browser global scope, and native_js/native_js_call escape hatches for third-party libs - codegen-js.el: destructure all new builtins in generated preamble; add @async decorator support that emits async function + await at call sites for known-async HTTP builtins and user-declared @async functions; pre- registration pass ensures forward calls to @async functions get await - spec/codegen-js.md: mark Phase 3 (DOM bridge) implemented, document @async approach and its limitations, update builtin table and status - examples/browser-counter.el: canonical example showing dom_get_element, dom_set_text, dom_is_null, window_set, and state_set/get
42 lines
1.4 KiB
EmacsLisp
42 lines
1.4 KiB
EmacsLisp
// browser-counter.el — canonical browser DOM bridge example
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//
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// Compile with: elc --target=js examples/browser-counter.el > counter.js
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//
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// Then include in an HTML page that has a <span id="count-display"> element.
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// The page can call window.increment() from any onclick handler, e.g.:
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// <button onclick="increment()">+1</button>
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//
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// On load the display is initialised to "0". Each call to increment()
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// adds 1 and updates the display text.
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//
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// Demonstrates:
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// - dom_get_element to locate a DOM node by id
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// - dom_set_text to update visible text content
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// - dom_is_null to guard against missing elements
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// - window_set to expose an El function for inline event handlers
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// - state_set/get for in-memory counter state (survives calls, resets
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// on page reload — same semantics as the C state_* API)
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fn init() -> Void {
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state_set("counter", 0)
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let display = dom_get_element("count-display")
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if !dom_is_null(display) {
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dom_set_text(display, "0")
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}
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}
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fn increment() -> Void {
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let current = str_to_int(state_get("counter"))
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let next = current + 1
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state_set("counter", next)
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let display = dom_get_element("count-display")
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if !dom_is_null(display) {
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dom_set_text(display, int_to_str(next))
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}
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}
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fn main() -> Void {
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init()
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window_set("increment", increment)
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}
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