Union types not supported in PHP ^7.3

[tdiam]

Description

Union types (like array|string) were introduced in PHP 8.0, so the package breaks in PHP ^7.3.

Steps to Reproduce

1. Copy the README code to a WordPress codebase.
2. Run with PHP 7.x.

Expected behavior:

Runs properly.

Actual behavior:

Fatal error: Uncaught Error: syntax error, unexpected '|', expecting variable (T_VARIABLE)

Versions

All versions.

[idleberg]

Thank you, I had no idea and followed my TypeScript habbits. I have removed the union types temporarily in v0.3.1 and plan to re-introduce them in November, when the minimum version will be bumped to PHP 8.0. Looking at the supported versions, I will also bump the minimum version to PHP 7.4 in the next release.