|
|
A compiler performs specific mathematical or logical manipulations. The following types of operators are provided by Objective C:
Some of the arithmetic operators that supported by Objective are shown in the given table. Assume variable A holds 10 and variable B holds 20, then:
Operator | Description | Example |
---|---|---|
+ | Adds two operands | A + B will give 30 |
- | Subtracts second operand from the first | A - B will give -10 |
* | Multiplies both operands | A * B will give 200 |
/ | Divides numerator by denominator | B / A will give 2 |
% | Modulus Operator and remainder of after an integer division | B % A will give 0 |
++ | Increment operator increases integer value by one | A++ will give 11 |
-- | Decrement operator decreases integer value by one | A-- will give 9 |
Relational operators that supported by Objective C are shown in the given table. Assume variable A holds 10 and variable B holds 20, then:
Operator | Description | Example |
---|---|---|
== | Checks if the values of two operands are equal or not; if yes, then condition becomes true. | (A == B) is not true. |
!= | Checks if the values of two operands are equal or not; if values are not equal, then condition becomes true. | (A != B) is true. |
> | Checks if the value of left operand is greater than the value of right operand; if yes, then condition becomes true. | (A > B) is not true. |
< | Checks if the value of left operand is less than the value of right operand; if yes, then condition becomes true. | (A < B) is true. |
>= | Checks if the value of left operand is greater than or equal to the value of right operand; if yes, then condition becomes true. | (A >= B) is not true. |
<= | Checks if the value of left operand is less than or equal to the value of right operand; if yes, then condition becomes true. | (A <= B) is true. |
Logical operators supported by Objective C language are listed in the below table. Assume variable A holds 1 and variable B holds 0, then:
Operator | Description | Example |
---|---|---|
&& | Called Logical AND operator. If both the operands are non zero then condition becomes true. | (A && B) is false. |
|| | Called Logical OR Operator. If any of the two operands is non zero then condition becomes true. | (A || B) is true. |
! | Called Logical NOT Operator. Use to reverses the logical state of its operand. If a condition is true, then Logical NOT operator will make false. | !(A && B) is true. |
Bitwise operator performs bit by bit operations. The truth tables for &, |, and ^ are as follows:Example
p | q | p & q | p | q | p ^ q |
---|---|---|---|---|
0 | 0 | 0 | 0 | 0 |
0 | 1 | 0 | 1 | 1 |
1 | 1 | 1 | 1 | 0 |
1 | 0 | 0 | 1 | 1 |
Assume if A = 60; and B = 13; They are represented in binary format as follows:
A = 0011 1100
B = 0000 1101
-----------------
A&B = 0000 1100
A|B = 0011 1101
A^B = 0011 0001
~A = 1100 0011
The Bitwise operators supported by Objective-C are listed in the below table. Assume variable A holds 60 and variable B holds 13 then:
Operator | Description | Example |
---|---|---|
& | Binary AND Operator copies a bit to the result if it exists in both operands. | (A & B) will give 12, which is 0000 1100 |
| | Binary OR Operator copies a bit if it exists in either operand. | (A | B) will give 61, which is 0011 1101 |
^ | Binary XOR Operator copies the bit if it is set in one operand but not both. | (A ^ B) will give 49, which is 0011 0001 |
~ | Binary Ones Complement Operator is unary and has the effect of 'flipping' bits. | (~A ) will give -61, which is 1100 0011 in 2's complement form. |
<< | Binary Left Shift Operator. The left operands value is moved left by the number of bits specified by the right operand. | A << 2 will give 240, which is 1111 0000 |
>> | Binary Right Shift Operator. The left operands value is moved right by the number of bits specified by the right operand. | A >> 2 will give 15, which is 0000 1111 |
Assignment operators supported by Objective C are listed below:
Operator | Description | Example |
---|---|---|
= | Simple assignment operator, Assigns values from right side operands to left side operand | C = A + B will assign value of A + B into C |
+= | Add AND assignment operator, It adds right operand to the left operand and assigns the result to left operand | C += A is equivalent to C = C + A |
-= | Subtract AND assignment operator, It subtracts right operand from the left operand and assigns the result to left operand | C -= A is equivalent to C = C - A |
*= | Multiply AND assignment operator, It multiplies right operand with the left operand and assigns the result to left operand | C *= A is equivalent to C = C * A |
/= | Divide AND assignment operator, It divides left operand with the right operand and assigns the result to left operand | C /= A is equivalent to C = C / A |
%= | Modulus AND assignment operator, It takes modulus using two operands and assigns the result to left operand | C %= A is equivalent to C = C % A |
<<= | Left shift AND assignment operator | C <<= 2 is same as C = C << 2 |
>>= | Right shift AND assignment operator | C >>= 2 is same as C = C >> 2 |
&= | Bitwise AND assignment operator | C &= 2 is same as C = C & 2 |
^= | bitwise exclusive OR and assignment operator | C ^= 2 is same as C = C ^ 2 |
|= | bitwise inclusive OR and assignment operator | C |= 2 is same as C = C | 2 |
Some of the other operators including sizeof and ? : supported by Objective-C Language.
Operator | Description | Example |
---|---|---|
sizeof() | Returns the size of an variable. | sizeof(a), where a is integer, will return 4. |
& | Returns the address of an variable. | &a; will give actual address of the variable. |
* | Pointer to a variable. | *a; will pointer to a variable. |
? : | Conditional Expression | If Condition is true ? Then value X : Otherwise value Y |
Grouping of terms in an expression is determined by operator precedence. The operators have higher precedence than others depends on how the expression I is evaluated.
For example, x = 7 + 3 * 2; here, x is assigned 13, not 20 because operator * has higher precedence than +, so it first gets multiplied with 3*2 and then adds into 7.
The operators with the highest precedence appear at the top of the table; those with the lowest appear at the bottom. Within an expression.The higher precedence operators will be evaluated first.
Examples
Category | Operator | Associativity |
---|---|---|
Postfix | () [] -> . ++ - - | Left to right |
Unary | + - ! ~ ++ - - (type)* & sizeof | Right to left |
Multiplicative | * / % | Left to right |
Additive | + - | Left to right |
Shift | << >> | Left to right |
Relational | < <= > >= | Left to right |
Equality | == != | Left to right |
Bitwise XOR | ^ | Left to right |
Bitwise OR | | | Left to right |
Logical AND | && | Left to right |
Logical OR | || | Left to right |
Conditional | ?: | Right to left |
Assignment | = += -= *= /= %=>>= <<= &= ^= |= | Right to left |
Comma | , | Left to right |
|
|
All rights reserved © 2020 Wisdom IT Services India Pvt. Ltd
Wisdomjobs.com is one of the best job search sites in India.