Defines a single function for an object.
Syntax
struct JSFunctionSpec {
const char *name;
JSNativeWrapper call;
uint16_t nargs;
uint16_t flags;
const char *selfHostedName;
};
typedef struct JSNativeWrapper {
JSNative op;
const JSJitInfo *info;
} JSNativeWrapper;
| Name | Type | Description |
|---|---|---|
name |
const char * |
The function's name. |
call |
JSNativeWrapper |
The built-in JS call wrapped by this function. If the function does not wrap a native JS call, set this value to NULL. |
nargs |
uint16_t |
The value used for Function.length. This no longer guarantees anything about the vp array. |
flags |
uint16_t |
The bitwise OR of any number of function flags. |
selfHostedName |
const char * |
The function's name in Self-Hosted JavaScript code. |
Description
JSFunctionSpec defines the attributes for a single JS function to associate with an object. An application typically has an array of JSFunctionSpec to define all the functions for an object and calls JS_DefineFunctions or JS_InitClass to create the functions and assign them to an object.
JSFunctionSpec can also be used to define an array element rather than a named property. Array elements are actually individual properties. To define an array element, cast the element's index value to const char*, initialize the name field with it, and specify the JSPROP_INDEX attribute in flags.
To define an array of JSPropertySpec, use JS_FS, JS_FN, JS_SYM_FN, JS_FNINFO, JS_SELF_HOSTED_FN, JS_SELF_HOSTED_SYM_FN, JS_SYM_FNSPEC, JS_FNSPEC, and JS_FS_END.