Objective-C

The registry row this page is generated from

Read at render time from the same family row the register reads, so nothing in this block can disagree with it.

Extensions

.m, .mm, .h

Registry names

objective-c

Recorded symbols

classes · protocols · methods

Relationship types this analyzer constructs

11 of 14 constructed, read from this analyzer's source and re-derived by the languages gate. Each row below is one of the engine's types, in the engine's own order.

11 constructed, 3 not constructed. All 3 absent types are recorded as ruled absent: the written reason and the corpus measurement behind each are in this family's completeness record. The register explains what each label means.

What this analyzer does not resolve

• The unit is the .m file: a header in the same project is a separate parse, so an instance variable declared there reads as undeclared here and an override of a base named in that header falls back to a first-parent guess at reduced confidence.
• A message send is recorded by selector name, not by a resolved receiver type. Nothing follows respondsToSelector: or a runtime-typed object, so dynamic dispatch is an edge to a name.
• An @class forward declaration and an @protocol(P) type query produce no symbol and no edge at all.

Every line above was written against Objective-C’s own analyzer module and is named against a construct in it, so it can be checked against the source. Nothing here is inherited from a template, or from another language’s page.

Where you meet it in a repository

Recognised by extension — .m, .mm, .h. Everything below is about where those files actually sit in a working repository.

• An Objective-C library is a header plus a .m file, and the public surface lives in the header — the half the implementation file cannot see.
• Categories are how a project adds methods to a type it does not own, so the category file is a first-class place in the tree rather than a subclass.
• Most message sends target a framework type, so the far end of a call edge is usually a name with no declaration behind it.

Questions this index answers

Phrased as retrievals, because that is what an index can honestly do: it holds the symbols and the edges between them, and hands them back with the evidence attached.

1. Which methods does this category add to the class?
2. Which protocols does this class conform to?
3. Where is this selector sent from?
4. Which properties and instance variables does this implementation declare?

What the analyzer sees in code like this

#import <UIKit/UIKit.h>

@interface NSString (Trim) <NSCoding>   // bb records: extension NSString · protocol NSCoding
- (NSString *)bb_trim:(BOOL)compact;   // bb records: method bb_trim:
@end

@implementation MyCache { NSLock *_lock; }   // bb records: class MyCache · property _lock
- (void)storeImage:(UIImage *)image { [self clear]; }   // bb records: method storeImage:
@end

Symbols are stored with the file they came from and the bytes they span, so a hit points at a line rather than at a guess. The annotations in the sample are commentary for the reader, not strings the index would store.

Languages that turn up in the same repository

Application & systems — the count beside each name is how many relationship types that family’s analyzer constructs.

• TypeScript14 types
• JavaScript12 types
• Python11 types
• Rust14 types
• Go12 types
• Java10 types
• C++11 types
• C9 types
• C#11 types
• Swift11 types
• Kotlin11 types
• Dart13 types
• Zig8 types
• Visual Basic11 types
• VBA9 types