[misc] add FAQ.md (#5452)

Add FAQ addressing some typescript related problems. More to be added in the future.

diff --git a/FAQ.md b/FAQ.md
new file mode 100644 (file)
index 0000000..2b23de1
--- /dev/null
+++ b/FAQ.md
@@ -0,0 +1,28 @@
+# Frequently asked questions
+
+_This document is a work in progress and it is used to collect common questions._
+
+## How to import moment in TypeScript?
+
+### Have trouble importing moment?
+
+If your tsconfig.json contains the following config, you must do the default import workflow `import moment from 'moment'`:
+
+```json
+// tsconfig.json
+// https://www.typescriptlang.org/v2/docs/handbook/release-notes/typescript-2-7.html
+{ 
+  "compilerOptions": {
+    "esModuleInterop": true,
+    "allowSyntheticDefaultImports": true,
+  }
+}
+```
+
+If you don't have these config above, the default import won't work, and you'll continue to have to use `import * as moment from 'moment'`.
+
+Note: It is recommended to use `import moment from 'moment'`.
+
+### Case and Program
+
+Known cases so far: [#5444](https://github.com/moment/moment/issues/5444), [#5248](https://github.com/moment/moment/issues/5348) and [#5449](https://github.com/moment/moment/issues/5449).
\ No newline at end of file

diff --git a/README.md b/README.md
index a922aea24fcefc2171ee18837c499b71f224b9e3..96077622ccc7f3daf75aa3493fbc69cb43b41017 100644 (file)
--- a/README.md
+++ b/README.md
@@ -47,6 +47,10 @@ write to [ichernev](https://github.com/ichernev).
 
 In addition to contributing code, you can help to triage issues. This can include reproducing bug reports, or asking for vital information such as version numbers or reproduction instructions. If you would like to start triaging issues, one easy way to get started is to [subscribe to moment/moment on CodeTriage](https://www.codetriage.com/moment/moment).
 
+### Frequently asked questions
+
+See [FAQ.md](FAQ.md).
+
 ## License
 
 Moment.js is freely distributable under the terms of the [MIT license](https://github.com/moment/moment/blob/develop/LICENSE).