sloppy equality (==)

equality with type conversion.

⟩ ⟩ ⟩ ⟩ ⟩ sloppy (==)

perform equality testing that allows type conversion.

compare：strict equality (===)

does not imply equality

// ⭐️ `undefined` can be converted to `false`.
undefined == false     // false❗

== never its operands to

do not rely on == or ===

// ⭐️ sloppy equality (==)
null == undefined,  // true
0    == '0',        // true    ('0'   -> 0)
0    == false,      // true    (false -> 0)
1    == true,       // true    (true  -> 1)
'1'  == true,       // true    (true  -> 1, then '1' -> 1)
'0'  == false,      // true    (false -> 0, then '0' -> 0)

// ⭐️ convertibility doesn't imply equality
//   (undefined can be converted to false)
undefined == false, // false❗

Previousequality & inequality operator Nextstrict equality (===)

Last updated 2 years ago

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