RU math phrases, half/полтора constants, export button

- vocab: EN+RU aliases for abs/log/ln/round; RU already had sqrt/cbrt
- engine: "half"/"a half"/"one half"/"половина" → 0.5; "one and a half"/"полтора"/"полторы" → 1.5 as named constants; widen const union in parser/tokenizer/evaluator/registry
- export: ⤓ button in statusbar dropdown — copy sheet, save .sum, export .txt, print/PDF; write_text_file Tauri command; print media CSS hides chrome

index.html

@@ -30,6 +30,15 @@
         <div id="statusbar">
           <span id="rates-info" title=""></span>
           <span class="spacer"></span>
+          <div id="export-wrap">
+            <button id="export-btn" title="Export">⤓</button>
+            <div id="export-menu" class="hidden">
+              <button data-action="copy" data-i18n="exportCopy">Copy sheet</button>
+              <button data-action="save-sum" data-i18n="exportSum">Save as .sum</button>
+              <button data-action="export-txt" data-i18n="exportTxt">Export as text</button>
+              <button data-action="print" data-i18n="exportPrint">Print / PDF</button>
+            </div>
+          </div>
           <span id="total-line" title=""></span>
         </div>
       </main>

src-tauri/src/main.rs

@@ -37,6 +37,11 @@ fn safe_name(name: &str) -> bool {
     !name.is_empty() && !name.contains(['/', '\\', ':']) && !name.contains("..")
 }
 
+#[tauri::command]
+fn write_text_file(path: String, contents: String) -> Result<(), String> {
+    write_atomic(std::path::Path::new(&path), &contents)
+}
+
 /// write via a temp file + rename so a crash mid-write cannot corrupt the target
 fn write_atomic(path: &Path, contents: &str) -> Result<(), String> {
     let tmp = path.with_extension("tmp");
@@ -521,7 +526,8 @@ fn main() {
             get_launch_file,
             read_text_file,
             exit_app,
-            is_hidden_launch
+            is_hidden_launch,
+            write_text_file
         ])
         .setup(|app| {
             let handle = app.handle().clone();

src/engine/engine.test.ts

@@ -71,6 +71,23 @@ describe("arithmetic", () => {
     expect(calc("round(2.6)")).toBe("3");
     expect(calc("log(1000)")).toBe("3");
     expect(calc("ln(1)")).toBe("0");
+    // russian aliases
+    expect(calc("квадратный корень из 16")).toBe("4");
+    expect(calc("кубический корень из 27")).toBe("3");
+    expect(calc("модуль(-5)")).toBe("5");
+    expect(calc("логарифм(1000)")).toBe("3");
+    expect(calc("натуральный логарифм(1)")).toBe("0");
+    expect(calc("округлить(2.6)")).toBe("3");
+  });
+  it("fraction constants", () => {
+    expect(calc("a half")).toBe("0.5");
+    expect(calc("one half")).toBe("0.5");
+    expect(calc("половина")).toBe("0.5");
+    expect(calc("a half million")).toBe("500,000");
+    expect(calc("one and a half")).toBe("1.5");
+    expect(calc("полтора")).toBe("1.5");
+    expect(calc("полтора миллиона")).toBe("1,500,000");
+    expect(calc("полторы тысячи")).toBe("1,500");
   });
 });
 

src/engine/evaluator.ts

@@ -27,7 +27,12 @@ export function evaluate(node: Node, ctx: EvalCtx): Value {
     case "num":
       return qty(node.v, null, node.repr);
     case "const":
-      return qty(node.name === "pi" ? PI : E);
+      switch (node.name) {
+        case "pi": return qty(PI);
+        case "e": return qty(E);
+        case "half": return qty(new Decimal("0.5"));
+        case "onehalf": return qty(new Decimal("1.5"));
+      }
     case "var": {
       const v = ctx.vars.get(node.name);
       if (!v) throw new EvalError(`unknown variable ${node.name}`);

src/engine/parser.ts

@@ -16,7 +16,7 @@ export type ConvTarget =
 
 export type Node =
   | { k: "num"; v: Decimal; repr: NumeralRepr }
-  | { k: "const"; name: "pi" | "e" }
+  | { k: "const"; name: "pi" | "e" | "half" | "onehalf" }
   | { k: "var"; name: string }
   | { k: "date"; word: DateWord }
   | { k: "agg"; name: "sum" | "avg" | "prev" }

src/engine/registry.ts

@@ -32,7 +32,7 @@ export type Payload =
   | { t: "repr"; repr: NumeralRepr }
   | { t: "special"; name: "unix" | "todate" }
   | { t: "date"; word: DateWord }
-  | { t: "const"; name: "pi" | "e" };
+  | { t: "const"; name: "pi" | "e" | "half" | "onehalf" };
 
 interface PhraseEntry {
   lexemes: string[]; // raw, as in the phrase
@@ -172,6 +172,10 @@ export function buildRegistry(): Registry {
   for (const v of vocab.variants("Operations", "prev.variants")) reg.addPhrase(v, { t: "agg", name: "prev" }, { caseSensitive: false });
   for (const v of vocab.variants("Operations", "sqrt.variants")) reg.addPhrase(v, { t: "func", name: "sqrt" }, { caseSensitive: false });
   for (const v of vocab.variants("Operations", "cbrt.variants")) reg.addPhrase(v, { t: "func", name: "cbrt" }, { caseSensitive: false });
+  for (const v of vocab.variants("Operations", "abs.variants")) reg.addPhrase(v, { t: "func", name: "abs" }, { caseSensitive: false });
+  for (const v of vocab.variants("Operations", "ln.variants")) reg.addPhrase(v, { t: "func", name: "ln" }, { caseSensitive: false });
+  for (const v of vocab.variants("Operations", "log.variants")) reg.addPhrase(v, { t: "func", name: "log" }, { caseSensitive: false });
+  for (const v of vocab.variants("Operations", "round.variants")) reg.addPhrase(v, { t: "func", name: "round" }, { caseSensitive: false });
   reg.addPhrase("mod", { t: "op", op: "mod" }, { caseSensitive: false });
   reg.addPhrase("modulo", { t: "op", op: "mod" }, { caseSensitive: false });
 
@@ -231,6 +235,12 @@ export function buildRegistry(): Registry {
   reg.addPhrase("π", { t: "const", name: "pi" });
   reg.addPhrase("пи", { t: "const", name: "pi" }, { caseSensitive: false });
   reg.addPhrase("e", { t: "const", name: "e" }, { caseSensitive: true });
+  reg.addPhrase("a half", { t: "const", name: "half" }, { caseSensitive: false });
+  reg.addPhrase("one half", { t: "const", name: "half" }, { caseSensitive: false });
+  reg.addPhrase("половина", { t: "const", name: "half" }, { caseSensitive: false });
+  reg.addPhrase("one and a half", { t: "const", name: "onehalf" }, { caseSensitive: false });
+  reg.addPhrase("полтора", { t: "const", name: "onehalf" }, { caseSensitive: false });
+  reg.addPhrase("полторы", { t: "const", name: "onehalf" }, { caseSensitive: false });
 
   for (const f of BUILTIN_FUNCS) reg.addPhrase(f, { t: "func", name: f }, { caseSensitive: false });
 

src/engine/tokenizer.ts

@@ -19,7 +19,7 @@ export type Token =
   | { t: "scale"; mult: Decimal; start: number; end: number }
   | { t: "repr"; repr: NumeralRepr; start: number; end: number }
   | { t: "date"; word: DateWord; start: number; end: number }
-  | { t: "const"; name: "pi" | "e"; start: number; end: number }
+  | { t: "const"; name: "pi" | "e" | "half" | "onehalf"; start: number; end: number }
   | { t: "lparen"; start: number; end: number }
   | { t: "rparen"; start: number; end: number }
   | { t: "semicolon"; start: number; end: number }

src/engine/vocab-data.ts

@@ -423,6 +423,10 @@ export const EN: VocabLocale = {
     "plus.variants": "with,plus,and",
     "prev.variants": "prev",
     "sqrt.variants": "sqrt,square root",
+    "abs.variants": "absolute value,absolute",
+    "ln.variants": "natural log,natural logarithm",
+    "log.variants": "logarithm",
+    "round.variants": "rounded",
     "sum.variants": "sum,total"
   },
   "Percent": {
@@ -889,6 +893,10 @@ export const RU: VocabLocale = {
     "plus.variants": "и,плюс,вместе с",
     "prev.variants": "пред.,пред",
     "sqrt.variants": "квадратный корень,кв корень,кв. корень",
+    "abs.variants": "модуль,абсолютное значение",
+    "ln.variants": "натуральный логарифм,нат. логарифм",
+    "log.variants": "логарифм",
+    "round.variants": "округлить,округление",
     "sum.variants": "всего,сумма,итог,итого"
   },
   "Percent": {

src/i18n.ts

@@ -42,6 +42,11 @@ const dict: Record<string, Record<string, string>> = {
     folderError: "Could not change the data folder",
     hotkeyFailed: "Hotkey is taken by another app",
     decimalsep: "Decimal separator",
+    exportCopy: "Copy sheet",
+    exportSum: "Save as .sum",
+    exportTxt: "Export as text",
+    exportPrint: "Print / PDF",
+    saved: "Saved",
   },
   ru: {
     settings: "Настройки",
@@ -84,6 +89,11 @@ const dict: Record<string, Record<string, string>> = {
     folderError: "Не удалось сменить папку данных",
     hotkeyFailed: "Хоткей занят другой программой",
     decimalsep: "Десятичный разделитель",
+    exportCopy: "Скопировать лист",
+    exportSum: "Сохранить как .sum",
+    exportTxt: "Экспорт в текст",
+    exportPrint: "Печать / PDF",
+    saved: "Сохранено",
   },
 };
 

src/main.ts

@@ -594,6 +594,41 @@ async function boot(): Promise<void> {
     }
   });
 
+  // export button + dropdown
+  const exportBtn = $("#export-btn");
+  const exportMenu = $("#export-menu");
+  exportBtn.addEventListener("click", (e) => {
+    e.stopPropagation();
+    exportMenu.classList.toggle("hidden");
+  });
+  document.addEventListener("click", () => exportMenu.classList.add("hidden"));
+  exportMenu.addEventListener("click", async (e) => {
+    const btn = (e.target as HTMLElement).closest<HTMLButtonElement>("[data-action]");
+    if (!btn) return;
+    exportMenu.classList.add("hidden");
+    const action = btn.dataset.action;
+    if (action === "copy") {
+      void navigator.clipboard.writeText(editor.getSheetWithResults());
+      toast(t("copied"));
+    } else if (action === "print") {
+      window.print();
+    } else if (isTauri()) {
+      const { save } = await import("@tauri-apps/plugin-dialog");
+      const { invoke } = await import("@tauri-apps/api/core");
+      const isSum = action === "save-sum";
+      const path = await save({
+        filters: isSum
+          ? [{ name: "Summarum Sheet", extensions: ["sum"] }]
+          : [{ name: "Text file", extensions: ["txt"] }],
+      });
+      if (path) {
+        const content = isSum ? editor.getText() : editor.getSheetWithResults();
+        await invoke("write_text_file", { path, contents: content });
+        toast(t("saved"));
+      }
+    }
+  });
+
   $("#rates-info").addEventListener("click", () => void refreshRates(true));
   setInterval(renderRatesInfo, 60_000);
 

src/ui/app.css

@@ -188,6 +188,51 @@ body {
 #total-line:hover { text-decoration: underline; }
 #total-line .total-label { color: var(--fg-muted); font-family: var(--font); margin-right: 8px; }
 
+/* ---------- export */
+#export-wrap { position: relative; }
+#export-btn {
+  background: none;
+  border: none;
+  cursor: pointer;
+  color: var(--fg-muted);
+  font-size: 15px;
+  padding: 0 4px;
+  line-height: 1;
+}
+#export-btn:hover { color: var(--fg); }
+#export-menu {
+  position: absolute;
+  bottom: calc(100% + 6px);
+  right: 0;
+  background: var(--toolbar-bg);
+  border: 1px solid var(--border);
+  border-radius: 6px;
+  box-shadow: 0 4px 16px rgba(0,0,0,0.18);
+  min-width: 160px;
+  padding: 4px 0;
+  z-index: 100;
+}
+#export-menu.hidden { display: none; }
+#export-menu button {
+  display: block;
+  width: 100%;
+  text-align: left;
+  background: none;
+  border: none;
+  padding: 7px 14px;
+  font-size: 13px;
+  color: var(--fg);
+  cursor: pointer;
+  font-family: var(--font);
+}
+#export-menu button:hover { background: var(--hover); }
+
+@media print {
+  #titlebar, #statusbar, #sidebar { display: none !important; }
+  #content { display: block; }
+  #editor-wrap { overflow: visible; height: auto; }
+}
+
 /* ---------- editor + results */
 #editor-wrap { position: relative; flex: 1; overflow: hidden; --results-width: 42%; }
 #editor { height: 100%; }