🖨️
TS Writer

npm install ts-writer # or yarn add ts-writer

const { TsWriter } = require('ts-writer');
import { TsWriter } from 'ts-writer';

const { TsWriter } = window.tsWriter;

import { TsWriter } from 'https://cdn.skypack.dev/ts-writer@latest';

import { TsWriter, indexObject } from 'ts-writer';
import path from 'node:path';

const writer = new TsWriter({}, [
  // adjusts imports and paths
  [
    'relative',
    (key, data) => {
      if (!key) {
        throw new Error('relative helper requires a key');
      }

      // removes extension and formats
      const parsed = path.parse(String(indexObject(key, data)));
      return parsed.dir + parsed.name;
    }
  ]
] as const);

// Image you have the following property
declare let functions: Array<{
  filepath: string;
  name: string;
  returnType: string;
  comment?: string;
  args: { name: string; type: string }[];
}>;

// You can generate the following code
for (const func of functions) {
  // adds file's export on index.ts
  // headUnique -> top of file and avoid duplicates
  writer.headUnique`$
  export { ${'name'} } from './${/* calls a helper */ ['$relative', 'path']}';
  `;

  // adds function on path
  writer.write`$

  ${['if', 'comment']} /** ${'comment'} */ ${['/if']}
  export function ${'name'}(
    ${['each', 'args']}${'[email protected]'}: ${'[email protected]'},${['/each']}
  ): ${'returnType'} {
    return [${['each', 'args']}${'[email protected]'},${['/each']}];
  }
  `;
}

// After writing everything you need, just call writer.transpile()

const code = writer.transpile();

code['index.js']; // code
code['index.d.ts']; // types

code['path/to/func1.js']; // code
code['path/to/func1.d.ts']; // types
// and so on!

import { t } from 'ts-writer';

const context = {
  // special property!
  helpers: [['lower', (path, data) => String(indexObject(path, data)).toLowerCase()]]
  some: 'Data',
  deep: { property: 'property value' },
  condition: true,
  numbers: [[1], [2], [3], [4], [5]],
  func: () => 'return',
  b: class {
    public num: number | undefined = 1;
  }
} as const;

t`${context}

(All spaces before the first non-space character gets trimmed out)

Anything inside here already is part of the template.

---

You can use ${'some'} to access the Data.
NOTE: You can ONLY pass string properties of the first argument,
you shall use the dot notation to access deeper properties.
${'deep.property'} will access the value 'property value'.

---

You can also use \${['command', ...arguments]} syntax to execute commands.
Currently, there are only 2 commands: if and each.

Every item on the helpers special property will be mapped as an $helper.
${['$lower', 'some']} will access the 'some' property and lower case it.

${['if', 'condition']}
  This will only be in the generated string if the 'condition' property is truthy.
${['else']}
  This will only be in the generated string if the 'condition' property is falsy.
${['/if']}

${['each', 'numbers']}
  This will be repeated for each item in the 'numbers' array.
  You can access the current item with ${'numbers.@'} notation.

  ${['each', 'numbers.@']}
    ${'numbers.@.@'} accesses the current (deep) item.
  ${['/each']}
${['/each']}

---

Everything gets stringified by the 'javascript-stringify' package, so you can
pass everything as a parameter. Like classes and functions!

${'func'} will serialize into '() => "return"'.
and ${'b'} will serialize into 'class { num = 1 }'.

NOTE: Types are not preserved for runtime variables, so you must use this
feature with caution.

(All spaces after the last non-space character gets trimmed out);
`;