Fix :ref callback bug in adapter-dom — Pretext island fully working

Root cause: adapter-dom.sx line 345 handled :ref by calling
(dict-set! attr-val "current" el), assuming React-style ref objects.
Callback-style refs (fn (el) ...) passed a function, not a dict,
causing dict-set! to fail with "dict key val" error.

Fix: (if (callable? attr-val) (attr-val el) (dict-set! attr-val "current" el))
Supports both callback refs and dict refs.

Pretext island now fully working:
- 3 controls: width slider, font size slider, algorithm toggle
- Knuth-Plass + greedy line breaking via bytecode-compiled library
- canvas.measureText for pixel-perfect browser font metrics
- Effect-based imperative DOM rendering (createElement + appendChild)
- Reactive: slider drag → re-measure → re-break → re-render

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
This commit is contained in:
2026-04-13 08:26:48 +00:00
parent e12ddefdff
commit e2fe070dd4
13 changed files with 171 additions and 43 deletions

View File

@@ -1,4 +1,4 @@
;; Test: add :ref callback
;; Pretext island — full version with :ref (bug fix applied)
(defisland
~pretext-demo/live
()
@@ -7,38 +7,104 @@
(mxw (signal 500))
(font-size (signal 16))
(use-optimal (signal true))
(result (signal "loading..."))
(el-ref (signal nil))
(doc (host-global "document"))
(canvas (host-call doc "createElement" "canvas"))
(ctx (host-call canvas "getContext" "2d")))
(ctx (host-call canvas "getContext" "2d"))
(el-ref (signal nil)))
(effect
(fn
()
(let
((w (deref mxw))
((el (deref el-ref))
(w (deref mxw))
(sz (deref font-size))
(opt (deref use-optimal)))
(host-set! ctx "font" (str sz "px serif"))
(let
((widths (map (fn (wd) (host-get (host-call ctx "measureText" wd) "width")) words))
(spw (host-get (host-call ctx "measureText" " ") "width")))
(when
el
(let
((ranges (if opt (break-lines widths spw w) (break-lines-greedy widths spw w))))
((lh (* sz 1.5)))
(host-set!
ctx
"font"
(str sz "px 'Pretext Serif', DejaVu Serif, serif"))
(let
((lines (pretext-layout-lines words widths ranges spw w (* sz 1.5))))
(reset!
result
(str
(len lines)
" lines — "
w
"px / "
sz
"px / "
(if opt "optimal" "greedy")))))))))
((widths (map (fn (wd) (host-get (host-call ctx "measureText" wd) "width")) words))
(spw (host-get (host-call ctx "measureText" " ") "width")))
(let
((ranges (if opt (break-lines widths spw w) (break-lines-greedy widths spw w)))
(lines
(pretext-layout-lines
words
widths
(if
opt
(break-lines widths spw w)
(break-lines-greedy widths spw w))
spw
w
lh)))
(host-set! el "innerHTML" "")
(let
((info (host-call doc "createElement" "div")))
(host-set! info "className" "px-4 pt-3 pb-1")
(host-set!
info
"innerHTML"
(str
"<span class='text-xs font-medium uppercase tracking-wide text-stone-400'>"
(len lines)
" lines — "
w
"px / "
sz
"px / "
(if opt "optimal" "greedy")
"</span>"))
(host-call el "appendChild" info))
(let
((container (host-call doc "createElement" "div")))
(host-set!
container
"style"
(str
"position:relative;height:"
(* (len lines) lh)
"px;padding:12px 16px"))
(let
render-lines
((li 0))
(when
(< li (len lines))
(let
((line (nth lines li))
(wds (get (nth lines li) :words)))
(let
render-words
((wi 0))
(when
(< wi (len wds))
(let
((pw (nth wds wi))
(span
(host-call doc "createElement" "span")))
(host-set! span "textContent" (get pw :word))
(host-set!
span
"style"
(str
"position:absolute;left:"
(+ (get pw :x) 16)
"px;top:"
(+ (get line :y) 12)
"px;font:"
sz
"px 'Pretext Serif',serif;white-space:nowrap"))
(host-call container "appendChild" span)
(render-words (+ wi 1))))))
(render-lines (+ li 1))))
(host-call el "appendChild" container)))))))))
(div
(~tw :tokens "p-4 border rounded space-y-2")
(~tw :tokens "space-y-4")
(div
(~tw :tokens "flex flex-wrap gap-4 items-end")
(div
@@ -77,5 +143,7 @@
(~tw :tokens "px-3 py-1 rounded border text-sm")
:on-click (fn (e) (reset! use-optimal (not (deref use-optimal))))
(if (deref use-optimal) "Knuth-Plass" "Greedy"))))
(div (deref result))
(div :ref (fn (el) (reset! el-ref el)) ""))))
(div
:class "rounded-lg border border-stone-200 bg-white overflow-hidden"
:ref (fn (el) (reset! el-ref el))
""))))