feat: add utils and code languages

Author: EndBug

src/index.ts

@@ -1,2 +1,3 @@
 export * as Blocks from './builders';
 export * as Types from './types';
+export * as Utils from './utils';

src/types.ts

@@ -1 +1,4 @@
+import {Code} from 'notion-api-types/responses/blocks';
+
 export * from 'notion-api-types';
+export type CodeLang = Code['code']['language'];

src/utils.ts

@@ -0,0 +1,84 @@
+import {CodeLang} from './types';
+
+/** This is just to keep a value with all languages, so that is can be used at runtime */
+const codeLangs: Record<CodeLang, null> = {
+  abap: null,
+  arduino: null,
+  bash: null,
+  basic: null,
+  c: null,
+  clojure: null,
+  coffeescript: null,
+  'c++': null,
+  'c#': null,
+  css: null,
+  dart: null,
+  diff: null,
+  docker: null,
+  elixir: null,
+  elm: null,
+  erlang: null,
+  flow: null,
+  fortran: null,
+  'f#': null,
+  gherkin: null,
+  glsl: null,
+  go: null,
+  graphql: null,
+  groovy: null,
+  haskell: null,
+  html: null,
+  java: null,
+  javascript: null,
+  json: null,
+  julia: null,
+  kotlin: null,
+  latex: null,
+  less: null,
+  lisp: null,
+  livescript: null,
+  lua: null,
+  makefile: null,
+  markdown: null,
+  markup: null,
+  matlab: null,
+  mermaid: null,
+  nix: null,
+  'objective-c': null,
+  ocaml: null,
+  pascal: null,
+  perl: null,
+  php: null,
+  'plain text': null,
+  powershell: null,
+  prolog: null,
+  protobuf: null,
+  python: null,
+  r: null,
+  reason: null,
+  ruby: null,
+  rust: null,
+  sass: null,
+  scala: null,
+  scheme: null,
+  scss: null,
+  shell: null,
+  sql: null,
+  swift: null,
+  typescript: null,
+  'vb.net': null,
+  verilog: null,
+  vhdl: null,
+  'visual basic': null,
+  webassembly: null,
+  xml: null,
+  yaml: null,
+  'java/c/c++/c#': null,
+};
+
+/**
+ * Returns whether a string is a supported language for `code` blocks
+ */
+export function isCodeLang(str: string): str is CodeLang {
+  return Object.keys(codeLangs).includes(str);
+}