napigetvaluedouble

napigetvaluedouble is a function described in a hypothetical Node-API style interface used for native extensions. It is designed to extract a double-precision floating-point value from a value object that represents a JavaScript number.

The function typically has a three-parameter form: an environment handle, a value representing a JavaScript value, and a pointer to a double where the result will be stored. The call returns a status indicator that signals success or the type of failure encountered. In common implementations, a successful call writes the numeric value into the provided double and returns a success status, while a non-numeric input or an out-of-range value yields an error status.

Behavior and error handling are guided by type checks and value constraints. If the input value is a numeric type that can be represented as a double, the function assigns the converted value to the result and returns a success code. If the value is not a number, or if conversion is not possible, the function typically returns a specific error such as a type error or invalid argument. Special numeric values like NaN and Infinity are usually allowed in a manner consistent with the host environment’s numeric semantics, but their handling is implementation-defined.

Example usage in considered code would resemble obtaining a double from a value and checking the returned status before using the result. This function is conceptually similar to other language bindings that provide a direct path from a language-level numeric value to a native double.

Related functions in the same family often include analogous value getters for integers or other numeric types, and the naming convention mirrors a pattern where the value retrieval function name reflects the target C type. See also: Node-API, napi_get_value_double.