Release v0.19.0

Features

• Add AST node IDs to types.Err for errorable expressions [#862]
• Set membership test rewriting optimizer [#865]
• Introduce 'wither' method for changing type traits [#871]
• Add option to include test types in the repl [#855]

Fixes

• Fix MaxID to consider macro keys and expressions [#861]
• Update builtin macros to use unique IDs. [#866]
• Fix incorrect example in string formatting docs. [#873]
• Fix the optional type name and type identifier resolution [#870]
• Fix type substitution within parameterized type names [#880]
• Bump follow-redirects from 1.15.2 to 1.15.4 in /repl/appengine/web [882]

New Contributors

• @nicksnyder made their first contribution in #873

Full Changelog: v0.18.2...v0.19.0