Boolean types and values
Boolean Mac OS historic type, sizeof(Boolean)==1
bool Defined in stdbool.h, ISO C/C++ standard type
false Now defined in stdbool.h
true Now defined in stdbool.h
boolean_t t1 = 1;//int type
Boolean t2 = 1; //unsigned char type
BOOL t3 = 4;//YES or NO
bool t4 = 1;//true or false
NSAssert(t1, @"boolean_t t1 is NO");//通过测试
NSAssert(t2, @"boolean_t t2 is NO");//通过测试
NSAssert(t3, @"boolean_t t3 is NO");//通过测试
NSAssert(t4, @"boolean_t t4 is NO");//通过测试
bool 是int
BOOL 是char
bool b1 当b1>0 就=YES
BOOL b2 当b2=1 才=YES
所以框架都用BOOL
Boolean mac os上有历史意义的类型
boolean_t i386
补充一下
typedef signed char BOOL;
// BOOL is explicitly signed so @encode(BOOL) == "c" rather than "C"
// even if -funsigned-char is used.
boolean_t t1 = 1;//int type
Boolean t2 = 1; //unsigned char type
BOOL t3 = 4;//YES or NO
bool t4 = 1;//true or false
NSAssert(t1, @"boolean_t t1 is NO");//通过测试

NSAssert(t2, @"boolean_t t2 is NO");//通过测试
NSAssert(t3, @"boolean_t t3 is NO");//通过测试
NSAssert(t4, @"boolean_t t4 is NO");//通过测试