t27 basics 13: let, var and const

Where let, var and const live in a t27 spec and whether the name may change. Lesson 13 of the t27 basics course.

This page sets no cookie and sends nothing anywhere.

Where the numbers come from

The lesson spec public/t27/files/specs/basics/13_local_names.t27, compiled clean on 7 backends by public/t27/t27_compiler.wasm, whose tests pass in the site test runner
Compiler verdicts, error lines, code and counts quoted on this page are what the same wasm answered in node 22 when the course was authored; words without a run behind them are said to be read, not run