t27 basics 21: what gen-ts writes

The TypeScript the real t27 compiler wrote for the lesson spec, line by line next to its source. Lesson 21 of the t27 basics course.

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Where the numbers come from

The lesson spec public/t27/files/specs/basics/21_gen_ts.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