3 files changed, 32 insertions, 18 deletions
diff --git a/src/context.ts b/src/context.ts
index 7759215..e0c0fa5 100644
--- a/src/context.ts
+++ b/src/context.ts
@@ -5,7 +5,11 @@ import { Ctx } from './types'
 
 const RESULT_TYPE_NAME = '__$result'
 
-export const createContext = (): Ctx => {
+export interface CtxOptions {
+  filePath: string
+}
+
+export const createContext = (options: CtxOptions): Ctx => {
   const project = new Project({
     compilerOptions: {
       target: ScriptTarget.ES3,
@@ -14,13 +18,7 @@ export const createContext = (): Ctx => {
 
   const typeChecker = project.getTypeChecker()
 
-  const [filePath] = process.argv.slice(2)
-
-  if (!filePath) {
-    throw new Error('Must specify ts file to run')
-  }
-
-  const sourceFile = project.addSourceFileAtPath(path.resolve(filePath))
+  const sourceFile = project.addSourceFileAtPath(path.resolve(options.filePath))
 
   const entryPoint = sourceFile.getExportedDeclarations().get('main')?.[0]
 
diff --git a/src/eval.ts b/src/eval.ts
index dc33fbe..6b9ade0 100644
--- a/src/eval.ts
+++ b/src/eval.ts
@@ -11,6 +11,10 @@ const rl = readline.createInterface({
   terminal: false,
 })
 
+export const cleanup = () => {
+  rl.close()
+}
+
 const readLineFromStdin = (): Promise<string> =>
   new Promise((res) => rl.on('line', res))
 
diff --git a/src/index.ts b/src/index.ts
index 65349fc..01420c8 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -1,15 +1,27 @@
+import { program } from 'commander'
 import { createContext } from './context'
-import { evalList } from './eval'
+import { cleanup, evalList } from './eval'
 
-const main = async () => {
-  const ctx = createContext()
-  const resultType = ctx.entryPoint.getType()
-  const effects = resultType.isTuple()
-    ? resultType.getTupleElements()
-    : [resultType]
-  await evalList(ctx, effects)
+const main = () => {
+  program
+    .name('ts-types-lang')
+    .description(`A runtime for typescript's type system that turns it into a general purpose, purely functional programming language!`)
+
+  program
+    .command('run')
+    .description('Run a typescript .ts file')
+    .argument('<file>', 'Typescript file to run')
+    .action(async (filePath) => {
+      const ctx = createContext({ filePath })
+      const resultType = ctx.entryPoint.getType()
+      const effects = resultType.isTuple()
+        ? resultType.getTupleElements()
+        : [resultType]
+      await evalList(ctx, effects)
+    })
+
+  return program.parseAsync()
 }
 
 main()
-  .then(() => process.exit(0))
-  .catch((e) => (console.error(e), process.exit(1)))
+  .finally(() => cleanup())