{ "componentChunkName": "component---src-templates-blog-post-js", "path": "/value-comparison-in-javascript/", "result": {"data":{"markdownRemark":{"html":"
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For comparing values, JavaScript provides three operations:

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Object.is(a, b)

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Object.is(a, b) tells us if a & b are the same value:

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console.log(Object.is(2, 2)) // true\n\nconsole.log(Object.is({}, {})) // false
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Object.is() is not specific to objects. It can compare any two values.

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{} always means create a new object value.

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Strict equality (===)

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Triple equals comparison (===) has the same behavior as Object.is() except the following two special cases:

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First special case

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Nan === NaN is false, although they are the same value.

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The reason NaN === NaN being false is largely historical.

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Second special case

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-0 === 0 & 0 === -0 are true, although they are different values.

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Floating point zero is either positively or negatively signed. This is useful in representing certain mathematical solutions, but as most situations don’t care about the difference between -0 & +0, strict equality treats them as the same value.

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Loose equality (==)

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Loose equality compares two values for equality after converting both values to a common type. After conversion, (one or both sides may undergo conversions), the final equality comparison is performed exactly as === performs it.

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However, in most cases, using loose equality is discouraged. The result of a comparison using strict equality is easier to predict and may evaluate more quickly due to lack of type coercion.

\n","frontmatter":{"title":"Value Comparison in JavaScript","date":"2021-07-20"}}},"pageContext":{"slug":"/value-comparison-in-javascript/","prev":{"fields":{"slug":"/declarative-vs-imperative-programming/"},"frontmatter":{"modules":null}},"next":{"fields":{"slug":"/implementing-a-stack-data-structure-in-javascript/"},"frontmatter":{"modules":null}}}}, "staticQueryHashes": ["3159585216"]}