ts2gas

A function that transpiles TypeScript to Google Apps Script.

``ts
ts2gas(code: string, transpileOptions?: ts.TranspileOptions): string
`

For example the code below

`ts
const writeToLog = (message: string) => console.info(message);

let words = ['hello', 'world'];
writeToLog(${words.join(' ')});
`

gets transpiled into

`javascript
// Compiled using ts2gas 1.3.0 (TypeScript 3.2.2)
var exports = exports || {};
var module = module || { exports: exports };
var writeToLog = function (message) { return console.info(message); };
var words = ['hello', 'world'];
writeToLog("" + words.join(' '));
`

Install

`shell
yarn add ts2gas
`

Usage

Write Apps Script as TypeScript without including any imports.

`ts
const ts2gas = require('ts2gas');

let transpiled = ts2gas(
function buildName(first:string, last:string) {
return \\${firstName} \${lastName}\;
}
);

// Transpiles to:
// function buildName(first, last) {
// return firstName + " " + lastName;
// }
`

$3

Transpiler is called with this default ts.TranspileOptions object

`ts
{
compilerOptions: {
experimentalDecorators: true,
isolatedModules: true,
module: "None",
noImplicitUseStrict: true,
noLib: true,
noResolve: true,
target: "ES3",
},
// the following property is to document this little known feature
// renamedDependencies: { SomeName: 'SomeOtherName' },
}
`

ts2gas can accepts a custom ts.TranspileOptions object as second parameter.

`ts
ts2gas(source: string, transpileOptions: ts.TranspileOptions = {}): string
`

Note that the following compilerOptions cannot be changed:

`ts
{
isolatedModules: true,
module: "None",
noLib: true,
noResolve: true,
}
`

TypeScript Tests

Some samples of TypeScript derived from

`ts
class Hamburger {
constructor() {
// This is the constructor.
}
listToppings() {
// This is a method.
}
}

// Template strings
var name = 'Grant';
var age = 42;
console.log(Hello! My name is ${name}, and I am not ${age} years old.);

// Rest args
const add = (a, b) => a + b;
let args = [3, 5];
add(...args); // same as \add(args[0], args[1])\, or \add.apply(null, args)\

// Spread array
let cde = ['c', 'd', 'e'];
let scale = ['a', 'b', ...cde, 'f', 'g']; // ['a', 'b', 'c', 'd', 'e', 'f', 'g']

// Spread map
let mapABC = { a: 5, b: 6, c: 3};
let mapABCD = { ...mapABC, d: 7}; // { a: 5, b: 6, c: 3, d: 7 }

// Destructure
let jane = { firstName: 'Jane', lastName: 'Doe'};
let john = { firstName: 'John', lastName: 'Doe', middleName: 'Smith' }
function sayName({firstName, lastName, middleName = 'N/A'}) {
console.log(Hello ${firstName} ${middleName} ${lastName})
}
sayName(jane) // -> Hello Jane N/A Doe
sayName(john) // -> Helo John Smith Doe

// Export
export const pi = 3.141592;
function add(x: number, y: number): number {
return x + y;
}
console.log(add(2, 2)); // 4

// Decorators
function Override(label: string) {
return function (target: any, key: string) {
Object.defineProperty(target, key, {
configurable: false,
get: () => label
});
}
}
class Test {
@Override('test') // invokes Override, which returns the decorator
name: string = 'pat';
}
let t = new Test();
console.log(t.name); // 'test'
``