Objc Coding Practices

Objective-C Coding Practices

Application skill for Objective-C style learning (from the archived awesome-guidelines style capsules). Follow Apple Cocoa Coding Guidelines plus project clang-format; GitHub tab legacy trees normalize via formatter over time.

Core Principle

Objective-C quality is prefixed, documented headers with explicit ownership, copy immutables, designated inits, NSError for expected failures.

When to Use / NOT

• iOS/macOS ObjC and ObjC++ (.m, .mm) libraries and app code.
• Setting up clang-format, clang-tidy, OCLint, Xcode analyze in CI.

NOT when:

• Swift-only modules, use Swift style foundations.
• Generated ObjC stubs, validate generators.

Workflow

1. Layout, indent, braces, imports (objc-style-formatting-layout.md).
2. Naming, prefixes, categories (objc-style-naming-prefixes.md).
3. Memory, properties, init, copy (objc-style-properties-memory.md).
4. Docs/errors, Doxygen, NSError (objc-style-docs-errors.md).
5. Verify, clang-format, analyzer, header doc audit on exports.

Red Flags

• Two-letter class prefix
• Unprefixed category methods on shared types
• getFoo accessor naming
• Dot syntax on non-property methods
• Missing memory semantics on properties
• @synthesize without compiler requirement
• Iv ar access outside init/dealloc/custom accessor
• Messaging self in -init/-dealloc for overridable selectors
• +new usage
• Redundant ivar nil/zero initialization in init
• Individual Foundation subheaders instead of umbrella import
• #include on ObjC headers
• Unsigned down-count loops
• Macro constants where static const suffices
• Exceptions for normal control flow
• Undocumented public methods/properties
• Returning mutable where immutable contract promised
• No copy of mutable args in setters/async
• Weak long-lived references (refactor target)
• Mixed selector wrapping styles in one file
• Tomdoc/Doxygen missing nil documentation on object params

Verification

• clang-format --dry-run / Xcode format on changed files
• xcodebuild analyze or project static analyzer
• Public header Doxygen/nil-contract audit
• Capsule checklist on prefix + designated initializer chain

References

• awesome-guidelines/references/objc-style-learning-note.md
• awesome-guidelines/references/objc-style-formatting-layout.md
• awesome-guidelines/references/objc-style-naming-prefixes.md
• awesome-guidelines/references/objc-style-properties-memory.md
• awesome-guidelines/references/objc-style-docs-errors.md