python literals via pyodide

bin/resolve-dependencies

@@ -86,6 +86,10 @@ const mains = ["unpkg", "jsdelivr", "browser", "main"];
     const package = await resolve("leaflet");
     console.log(`export const leaflet = dependency("${package.name}", "${package.version}", "${package.export.replace(/-src\.js$/, ".js")}");`);
   }
+  {
+    const package = await resolve("pyodide");
+    console.log(`export const pyodide = {resolve: () => "https://cdn.jsdelivr.net/pyodide/v${package.version}/full/pyodide.js"};`);
+  }
 })();
 
 async function resolve(specifier) {

src/dependencies.js

@@ -19,3 +19,4 @@ export const topojson = dependency("topojson-client", "3.1.0", "dist/topojson-cl
 export const exceljs = dependency("exceljs", "4.3.0", "dist/exceljs.min.js");
 export const mermaid = dependency("mermaid", "9.1.1", "dist/mermaid.min.js");
 export const leaflet = dependency("leaflet", "1.8.0", "dist/leaflet.js");
+export const pyodide = {resolve: () => "https://cdn.jsdelivr.net/pyodide/v0.20.0/full/pyodide.js"};

src/library.js

@@ -10,6 +10,7 @@ import mermaid from "./mermaid.js";
 import Mutable from "./mutable.js";
 import now from "./now.js";
 import Promises from "./promises/index.js";
+import py from "./py.js";
 import resolve from "./resolve.js";
 import requirer, {requireDefault, setDefaultRequire} from "./require.js";
 import SQLite, {SQLiteDatabaseClient} from "./sqlite.js";
@@ -44,6 +45,7 @@ export default Object.assign(Object.defineProperties(function Library(resolver)
     Inputs: () => require(inputs.resolve()).then(Inputs => ({...Inputs, file: Inputs.fileOf(AbstractFile)})),
     L: () => leaflet(require),
     mermaid: () => mermaid(require),
+    py: () => py(require),
     Plot: () => require(plot.resolve()),
     require: () => require,
     resolve: () => resolve, // deprecated; use async require.resolve instead

src/py.js

@@ -0,0 +1,18 @@
+import {pyodide as Pyodide} from "./dependencies.js";
+
+export default async function py(require) {
+  const pyodide = await (await require(Pyodide.resolve())).loadPyodide();
+  return async function py(strings, ...values) {
+    let globals = {};
+    const code = strings.reduce((code, string, i) => {
+      if (!(i in values)) return code + string;
+      const name = `_${i}`;
+      globals[name] = values[i];
+      return code + string + name;
+    }, "");
+    globals = pyodide.toPy(globals);
+    await pyodide.loadPackagesFromImports(code);
+    const value = await pyodide.runPythonAsync(code, {globals});
+    return pyodide.isPyProxy(value) ? value.toJs() : value;
+  };
+}

test/index-test.js

@@ -34,6 +34,7 @@ test("new Library returns a library with the expected keys", async t => {
     "now",
     "olympians",
     "penguins",
+    "py",
     "require",
     "resolve",
     "svg",