Add "get card field" command

src/3x5.ts

@@ -1,19 +1,8 @@
-import { ALL as HTML } from "./lib/html";
-import { parse } from "./parser";
-import { runNoctl, Vm } from "./vm";
-import { AsHtml, AsText, TextPiece } from "./words";
-
-/**
- * Basic unit of information, also an "actor" in the programming system
- */
-type Card = {
-  /** Unique identifier */
-  id: number;
-  /** Key-value properties on the card */
-  fields: Record<string, string>;
-  /** Eventually: a markdown string containing code, but for now, just code */
-  code: string;
-};
+import { Card, CardVm, GetField } from './lib/card';
+import { ALL as HTML } from './lib/html';
+import { parse } from './parser';
+import { runNoctl, Vm } from './vm';
+import { AsHtml, AsText, TextPiece } from './words';
 
 /**
  * Updates a card's fields
@@ -43,7 +32,7 @@ function parseFields(card: Card, fields: string) {
  * @param code Script to run
  * @returns Markup to render / output
  */
-function renderCard(state: Vm, code: string) {
+function renderCard(state: CardVm, code: string) {
   const script = parse(code);
   if (script[0]) {
     runNoctl(state, script[1], (word) => (state.output += AsHtml(word) + "\n"));
@@ -128,10 +117,11 @@ function render() {
   parseFields(theCard, fieldInput.value);
   theCard.code = codeInput.value;
 
-  const vm: Vm = {
+  const vm: CardVm = {
     mode: "render",
-    commands: { ...HTML },
+    commands: { ...HTML, get: GetField },
     output: "",
+    card: theCard,
   };
   const html = renderCard(vm, theCard.code);
 
@@ -145,7 +135,7 @@ document.body.append(
   fieldInput,
   codeInput,
   rerender,
-  state,
   display,
+  state,
   debugDisplay
 );

src/lib/card.ts

@@ -0,0 +1,25 @@
+import { Vm } from '../vm';
+import { TextPiece } from '../words';
+import { getOpt } from './options';
+
+/**
+ * Basic unit of information, also an "actor" in the programming system
+ */
+export type Card = {
+  /** Unique identifier */
+  id: number;
+  /** Key-value properties on the card */
+  fields: Record<string, string>;
+  /** Eventually: a markdown string containing code, but for now, just code */
+  code: string;
+};
+
+export type CardVm = Vm<{
+  card: Card;
+}>;
+
+export function GetField(vm: CardVm, argv: TextPiece[]): TextPiece {
+  const [{ error = false }, fieldName] = getOpt(argv, { min: 1, max: 1 });
+  // TODO: handle error
+  return { text: vm.card.fields[fieldName] ?? "" };
+}