Reading-Notes

My journal for Code Fellows

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Operators and Loops

JavaScript has both Binary and Unary Operators

Binary example - operand1 operator operand2
x * y

Unary example - operator operand
x++ or x–

The assignment operator assigns a value to its left operand based on the value of its right operand
Assignments also have shorthand that can also be used
When chaining expression the assignment expressions are grouped right to left and influenced by parentheses
Avoid putting a variable chain in const, let, and var statements as it often does not work

Assignment	x = f()	x = f()
Addition assignment	x += f()	x = x + f()
Subtraction assignment	x -= f()	x = x - f()
Multiplication assignment	x *= f()	x = x * f()
Division assignment	x /= f()	x = x / f()
Remainder assignment	x %= f()	x = x % f()
Exponentiation assignment	x **= f()	x = x ** f()
Left shift assignment	x «= f()	x = x « f()
Right shift assignment	x »= f()	x = x » f()
Unsigned right shift assignment	x »>= f()	x = x »> f()
Bitwise AND assignment	x &= f()	x = x & f()
Bitwise XOR assignment	x ^= f()	x = x ^ f()
Bitwise OR assignment	x	= f()	x = x	f()
Logical AND assignment	x &&= f()	x && (x = f())
Logical OR assignment	x		= f()	x	(x = f())
Logical nullish assignment	x ??= f()	x ?? (x = f())

Compares its operands and returns a logical value depending on whether the comparison is true

Equal (==)	Returns true if the operands are equal.
Not equal (!=)	Returns true if the operands are not equal.
Strict equal (===)	Returns true if the operands are equal and of the same type. See also Object.is and sameness in JS.
Strict not equal (!==)	Returns true if the operands are of the same type but not equal, or are of different type.
Greater than (>)	Returns true if the left operand is greater than the right operand.
Greater than or equal (>=)	Returns true if the left operand is greater than or equal to the right operand.
Less than (<)	Returns true if the left operand is less than the right operand.
Less than or equal (<=)	Returns true if the left operand is less than or equal to the right operand.

Start out with an initial expression
the condition expression will evaluate if it is true which determines if the loop continues
the increment expression will execute if present and repeat the loop process
Example - for(let i = 0; i < 5; i++) the initial variable i is equal to 0 and since the condition is true since 0 is less than 5 the code following will execute. Once all the code is executed i will be incrementally increased by 1 and the condition expression will be checked again

Will execute code until a specified condition evaluates to false
Example - for(x < y) the code following this for loop will repeatedly execute if x is less than y since the expression is true and will break only when x is greater than y which makes the expression false