Idioms, Style and Best Practices

48.1 The D Style Guide (Highlights)

4-space indentation, Allman braces (Phobos style), camelCase functions and variables, PascalCase types, lowercase modules.

Use dfmt for formatting and dscanner --styleCheck for linting.

✅ Use ranges and UFCS pipelines for data processing.

✅ Use auto for complex range types. Use const/immutable liberally.

✅ Mark functions @safe, pure, nothrow, @nogc where possible (at least @safe).

✅ Use structs for values and RAII. Use classes for polymorphic identity objects.

✅ Use scope(exit) instead of try/finally chains.

✅ Write unittest blocks next to the code. Use documented unittests as examples.

✅ Use enforce for runtime input validation and assert/contracts for programmer errors.

✅ Use local and selective imports to reduce compile times and namespace pollution.

✅ Use template constraints to document generic requirements.

✅ Use std.sumtype for variants, Nullable for optional values, Flag for boolean parameters.

✅ Keep @trusted blocks tiny and review them carefully.

❌ Don't catch Error. Don't rely on class destructors for deterministic cleanup.

❌ Don't overuse string mixins when template mixins or plain code suffice.

❌ Avoid __gshared except for C interop. Avoid casting away immutable.

❌ Don't ignore GC allocations in latency-sensitive code.

CI with GitHub Actions (dlang-community/setup-dlang), testing on DMD and LDC, multiple OSes, dub test, coverage (codecov), and dub lint.

Semantic versioning, dub.selections.json committed for applications, docs published (dub build -b ddox or adrdox).