2.8 Bitwise Operations

>>>

(0x01 | 0x03).toString(2)

"11"

The | (OR), & (AND), ^ (XOR) and ~ (NOT) bitwise operators uses a 32 bit integer representation of a number. Using toString(2) allows printing the result in binary.

>>>

(0x01 & 0x03).toString(2)

"1"

>>>

(0x01 ^ 0x03).toString(2)

"10"

>>>

(~0xECA86420).toString(16)

"13579bdf"

When using binary negation in particular, care must be taken to avoid conversions to and from the normal 64 bit floating-point representation of numbers, since this will often result in a negative number instead of the expected bit sequence.

>>>

(0xFFFF >> 4).toString(16)

"fff"

The << (left shift), >> (signed right shift) and >>> (unsigned right shift) operators allow moving the bits a number of steps in either direction.

>>>

var a = 1; a <<= 2; print(a);

The bitwise operators are also available as assignment operators: |=, &=, ^=, <<=, >>= and >>>=.

>>>

The console allows you to interact with the course material and examples. Use the following keys:

<Enter> — Execute the code
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A special logging function is also available:

print(value) — Prints a value to the console.
print(value, true) — Prints a debug version of a value.

Console Learner — An interactive JavaScript course.