# valid-typeof
Enforce the use of valid string literals in a typeof
comparison.
typeof
can only return a small set of strings, undefined
, object
,
boolean
, number
, string
or function
, and if you provide
an invalid value, it’s most likely a typo, and the comparison
will always return false
.
This behaviour will be denied by this rule.
# Invalid Code Examples
typeof foo === "strnig"
typeof foo == "undefimed"
typeof bar != "nunber"
typeof bar !== "fucntion"
# Config
Name | Type | Description |
---|---|---|
requireStringLiterals | bool | * If this option is true , typeof expression can only be compared* to valid string literals, or other typeof expressions, but* can not be compared to any other value. |
More incorrect examples
typeof foo === "strnig"
typeof foo == "undefimed"
typeof bar != "nunber"
typeof bar !== "fucntion"
More correct examples
typeof foo === "string"
typeof bar == "undefined"
typeof foo === baz
typeof foo === 4
typeof bar === typeof qux