Enhanced ObjC Coding Style Cheat Sheet (Version 1.0)

Compact version of the Enhanced ObjC Coding Style, extending the ObjC Coding Style Cheat Sheet and Enhanced C Coding Style Cheat Sheet.

1. Scope

• The standard ObjC Coding Style Cheat Sheet remains authoritative for normal Objective-C formatting and layout.
• The Enhanced C Coding Style Cheat Sheet remains authoritative for the shared wrapper layer.
• This cheat sheet covers only the enhanced Objective-C additions.

2. Activation and Wrapper Rules

• ObjC-only helpers are enabled automatically by begin_header / end_header and begin_impl / end_impl.
• Do not include begin_objc.h or end_objc.h directly in normal project code.
• Do not use the ObjC-only macros in plain C files.

3. Property Attribute Macros

• RO = nonatomic,readonly.
• RW = nonatomic,readwrite.
• A_RO = atomic,readonly.
• A_RW = atomic,readwrite.
• Prefer RO / RW by default. Use the atomic forms only intentionally.
• Combine them with normal property attributes when needed, for example @property(RW,weak) ....

4. Class and Member Attribute Macros

• final: class cannot be subclassed.
• private_methods: members use direct Objective-C dispatch.
• internal: shorthand for final private_methods.

5. Direct Method Attribute Macro

• direct_call: direct dispatch for one specific method.

6. Disabling Default Initializers

• no_default_inits: makes new and init unavailable. Use it when designated initializers are required.

7. ObjC Object Guard Macros

• Prefer guard_objc(...) { ... } endguard, return_unless_objc(...), continue_unless_objc(...), and break_unless_objc(...) when binding maybe-nil Objective-C objects.
• These macros bind assigned values as nonnull def locals after the nil check succeeds.
• guard_objc(...) supports the same optional trailing condition and else { ... } form as the shared guard(...).
• The shared return_unless(...), continue_unless(...), and break_unless(...) still remain appropriate for plain conditions and non-object values.

8. ObjC Casting Helper

• asOptClass(ClassName, obj) returns a typed object or nil.
• Use it with guard_objc(...) and the other ObjC guard macros for dynamic id inputs.

9. Weak and Strong Capture Helpers

• weak(var) creates weak_var before a block capture.
• strong(var) creates strong_var from weak_var inside the block.
• return_unless_strong(returnValue, var) is the common early-exit form when the strong rebound is required before continuing.

10. Preference Rule

• When normal Objective-C syntax and the enhanced ObjC layer are equivalent, prefer the project layer in this project.