Implement push command

src/vm/commands/index.ts

@@ -59,6 +59,7 @@ import {Unless} from "./unless.js";
 import {Convert} from "./convert.js";
 import {While} from "./while.js";
 import {Table} from "./table.js";
+import {Push} from "./push.js";
 
 export type Commands = Command<CommandData>[]
 export const commands: Commands = [
@@ -96,6 +97,7 @@ export const commands: Commands = [
     new Over,
     new Paste,
     new Prefix,
+    new Push,
     new Quote,
     new Redo,
     new Replace,

src/vm/commands/push.ts

@@ -0,0 +1,32 @@
+import {Command, ParseContext, StrTerm} from "./command.js";
+import {LexInput} from "../lexer.js";
+import {StrVM} from "../vm.js";
+
+export type PushData = {
+    val: StrTerm,
+}
+
+export class Push extends Command<PushData> {
+    async attemptParse(context: ParseContext): Promise<PushData> {
+        return {
+            val: await context.popTerm(),
+        }
+    }
+
+    getDisplayName(): string {
+        return 'push'
+    }
+
+    isParseCandidate(token: LexInput): boolean {
+        return this.isKeyword(token, 'push')
+    }
+
+    async execute(vm: StrVM, data: PushData): Promise<StrVM> {
+        return vm.replaceContextMatchingTerm(ctx => ({
+            destructured: parts => [
+                ...parts,
+                { value: ctx.resolveRequired(data.val) },
+            ],
+        }))
+    }
+}