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NSMethodSignature class reference

Authors

Andrew Kachites McCallum (mccallum@gnu.ai.mit.edu)

Version: 38691

Date: 2015-06-26 02:50:17 -0600 (Fri, 26 Jun 2015)

Copyright: (C) 1994-2015 Free Software Foundation, Inc.

Software documentation for the NSMethodSignature class

NSMethodSignature : NSObject

Declared in:
Foundation/NSMethodSignature.h
Availability: OpenStep

Class encapsulating type information for method arguments and return value. It is used as a component of NSInvocation to implement message forwarding, such as within the distributed objects framework. Instances can be obtained from the NSObject method [NSObject -methodSignatureForSelector:] .

Basically, types are represented as Objective-C @encode(...) compatible strings. The arguments are numbered starting from 0, including the implicit arguments self (type id, at position 0) and _cmd (type SEL, at position 1).

Method summary

signatureWithObjCTypes: 

+ (NSMethodSignature*) signatureWithObjCTypes: (const char*)t;
Availability: OpenStep

Build a method signature directly from string description of return type and argument types, using the Objective-C @encode(...) type codes.

frameLength 

- (NSUInteger) frameLength;
Availability: OpenStep

Number of bytes that the full set of arguments occupies on the stack, which is platform(hardware)-dependent.

getArgumentTypeAtIndex: 

- (const char*) getArgumentTypeAtIndex: (NSUInteger)index;
Availability: OpenStep

Returns Objective-C @encode(...) compatible string. Arguments are numbered starting from 0, including the implicit arguments self (type id, at position 0) and _cmd (type SEL, at position 1).
Type strings may include leading type qualifiers.

isOneway 

- (BOOL) isOneway;
Availability: OpenStep

Pertains to distributed objects; method is asynchronous when invoked and return should not be waited for.

methodReturnLength 

- (NSUInteger) methodReturnLength;
Availability: OpenStep

Number of bytes that the return value occupies on the stack, which is platform(hardware)-dependent.

methodReturnType 

- (const char*) methodReturnType;
Availability: OpenStep

Returns an Objective-C @encode(...) compatible string describing the return type of the method. This may include type qualifiers.

numberOfArguments 

- (NSUInteger) numberOfArguments;
Availability: OpenStep

Returns number of arguments to method, including the implicit self and _cmd.

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