ludic/packages/ludic.ui/tpl.ludic
Orkuncakilkaya 637d07400e feat(ui): ludic.ui grows toward HTML, CSS and React (Phase 0.U1-U4)
- Natives: ui_native(tag, measure, draw) makes an element the program draws itself; ui_fire
  runs its on-<event> with event.value. input, select and textarea have simple defaults.
- React:
  - keyed <each>, <let>, <provide> context through components, <fragment>;
  - named slots, default props on <component>;
  - on-mount / on-unmount;
  - inline text inside text elements.
- CSS:
  - custom properties and var();
  - position relative/absolute/fixed with insets and z-index;
  - em/rem/vw/vh and @media;
  - wrapping text and ellipsis, overflow;
  - + and ~ combinators, :nth-child(an+b), :checked, :active.
- Developing: errors with file:line, ui_errors(), ui_reload() keeping state, and an
  inspector-style ui_dump.
- view fields infer the type of a literal or a named function's result.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
2026-09-24 16:17:25 +03:00

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3.3 KiB
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# tpl.ludic - a template file read into what the builder walks: every attribute and every
# element's text an expression, every on-* attribute an action. A file holds <component>s and
# <screen>s under one root; a component is used as a tag of its own name anywhere after.
export property UiTpl {
tag: string = ""
keys: []string = null
vals: []UiExpr = null
on_keys: []string = null
on_acts: []UiAct = null
text: UiExpr = null
kids: []UiTpl = null
comp: UiTpl = null # the component this tag names, found when its file loads
sheet: UiSheet = null # the styles of the file it was written in
style: UiRule = null # its style="..." attribute, read as declarations
raw: string = "" # a <style>'s text, which is not a template's
where: string = "" # file:line, for an error
}
# the text being read, and where its lines start, so an element can say which line it is on
var tp_nl: []int = new []int
function tp_lines(src: string) -> void {
tp_nl = new []int
for i in 0 .. len(src) {
if src[i] == 10 { push(tp_nl, i) }
}
}
function tp_line(at: int) -> int {
var lo = 0
var hi = len(tp_nl)
while lo < hi {
let mid = (lo + hi) / 2
if tp_nl[mid] < at { lo = mid + 1 } else { hi = mid }
}
return lo + 1
}
function tpl_read(x: Xml, file: string) -> UiTpl {
let t = new UiTpl
t.tag = Xml.tag(x)
t.keys = new []string
t.vals = new []UiExpr
t.on_keys = new []string
t.on_acts = new []UiAct
t.kids = new []UiTpl
t.where = `{file}:{tp_line(x.at)}`
let err = new []string
for i in 0 .. len(x.akeys) {
let k: string = x.akeys[i]
let v: string = x.avals[i]
if len(k) > 3 and k[0..3] == "on-" {
push(t.on_keys, tpl_event(k[3..len(k)]))
push(t.on_acts, act_parse(v, err))
} else if k == "onclick" {
push(t.on_keys, "press")
push(t.on_acts, act_parse(v, err))
} else if k == "style" { t.style = lss_decls(v, err) } else {
push(t.keys, k)
push(t.vals, tpl_value(v, err))
}
}
for i in 0 .. Xml.child_count(x) { push(t.kids, tpl_read(Xml.child(x, i), file)) }
if t.tag == "style" {
t.raw = Xml.text(x)
return t
}
let words = tpl_words(Xml.text(x))
if len(words) > 0 and len(t.kids) == 0 { t.text = ex_text(words, err) }
for i in 0 .. len(err) { ui_err(`{t.where}: <{t.tag}> {err[i]}`) }
return t
}
# on-click is on-press, as a browser would have it
function tpl_event(name: string) -> string {
if name == "click" { return "press" }
return name
}
# an attribute: a plain number is a number, anything else text with {holes}
function tpl_value(v: string, err: []string) -> UiExpr {
var num = len(v) > 0
for i in 0 .. len(v) {
if not ((v[i] >= 48 and v[i] <= 57) or v[i] == 46 or (i == 0 and v[i] == 45)) { num = false }
}
if num { return ex_parse(v, err) }
return ex_text(v, err)
}
# text as a reader sees it: the ends trimmed and every run of white space one space
function tpl_words(s: string) -> string {
var out = ""
var gap = false
for i in 0 .. len(s) {
let c = s[i]
if c == 32 or c == 9 or c == 10 or c == 13 { gap = len(out) > 0 } else {
if gap { out = out + " " }
gap = false
out = out + s[i..i + 1]
}
}
return out
}
function tpl_attr(t: UiTpl, key: string) -> UiExpr {
for i in 0 .. len(t.keys) {
if t.keys[i] == key { return t.vals[i] }
}
return null
}