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Learn the various meanings and uses of the word operator, from one who operates a machine or device to a symbol that performs a mathematical or logical operation. See examples, synonyms, etymology, and related phrases of operator.
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Learn the meaning of operator as a person, a company, or a symbol in mathematics. Find out how to use operator in different contexts and collocations with examples from various sources.
Learn the meaning of operator in different contexts, such as a person, a company, a symbol, or a skill. Find out how to use operator in sentences and collocations with examples from the Cambridge Dictionary.
An operator operates, or controls, something. You could be a radio operator, a heavy machinery operator, or even a telephone operator — or you can be the operator, or manager, of a business. If you start your own dog walking company, you can call yourself an "owner-operator."
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The nullish coalescing (??) operator is a logical operator that returns its right-hand side operand when its left-hand side operand is null or undefined, and otherwise returns its left-hand side operand.
The nullish coalescing operator can be seen as a special case of the logical OR (||) operator. The latter returns the right-hand side operand if the left operand is any falsy value, not only null or undefined. In other words, if you use || to provide some default value to another variable foo, you may encounter unexpected behaviors if you consider some falsy values as usable (e.g., '' or 0). See below for more examples.
The nullish coalescing operator has the fifth-lowest operator precedence, directly lower than || and directly higher than the conditional (ternary) operator.
It is not possible to combine both the AND (&&) and OR operators (||) directly with ??. A syntax error will be thrown in such cases.
Instead, provide parenthesis to explicitly indicate precedence:
Using the nullish coalescing operator
In this example, we will provide default values but keep values other than null or undefined.
Assigning a default value to a variable
Earlier, when one wanted to assign a default value to a variable, a common pattern was to use the logical OR operator (||): However, due to || being a boolean logical operator, the left-hand-side operand was coerced to a boolean for the evaluation and any falsy value (including 0, '', NaN, false, etc.) was not returned. This behavior may cause unexpected consequences if you consider 0, '', or NaN as valid values. The nullish coalescing operator avoids this pitfall by only returning the second operand when the first one evaluates to either null or undefined (but no other falsy values):
Short-circuiting
Like the OR and AND logical operators, the right-hand side expression is not evaluated if the left-hand side proves to be neither null nor undefined.
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•Nullish coalescing assignment (??=)
•Optional chaining (?.)
•Logical OR (||)
•Default parameters
Learn the various meanings and uses of the word operator in English. Find out how it can refer to a person who operates something, connects calls, or achieves things easily.
noun. a person who operates a machine, apparatus, or the like: a telegraph operator. a person who operates a telephone switchboard, especially for a telephone company. a person who manages a working or industrial establishment, enterprise, or system: the operators of a mine.
