JSVAL_IS_STRING
determines if a given jsval is a string.
... syntax jsval_is_string(v) description jsval_is_string(v) is true if v is a string.
... to access the content of a string jsval, use jsval_to_string, js_getstringchars, and js_getstringlength.
...if (jsval_is_string(myitem)) { ...

JSVAL_NULL
the jsval that represents the javascript value null.
... syntax jsval_null description jsval_null is a jsval constant that represents the javascript value null.
... it is equivalent to object_to_jsval(null).
... see also mxr id search for jsval_null jsval_void jsval_true jsval_false jsval_zero jsval_one bug 1177825 -- removed ...

JSVAL_TO_BOOLEAN
syntax jsbool jsval_to_boolean(jsval v); description jsval_to_boolean casts the value v to a c integer, either 0 or 1.
... as a precondition, jsval_is_boolean(v) must be true.
... that is, v must be either jsval_true or jsval_false.
...to convert a jsbool to jsval, use boolean_to_jsval.

OBJECT_TO_JSVAL
syntax jsval object_to_jsval(jsobject *obj); name type description obj jsobject * a pointer to a javascript object to convert to a jsval.
... description object_to_jsval casts obj from type jsobject * to jsval.
... if obj is null, the result is jsval_null.
... see also mxr id search for object_to_jsval js_valuetoobject js::objectvalue js::objectornullvalue bug 1177892 -- removed ...

JSVAL_IS_BOOLEAN
determines if a given jsval is a javascript boolean.
... syntax jsval_is_boolean(v) description jsval_is_boolean(v) is true if the given javascript value, v, is a boolean value (that is, it is either jsval_true or jsval_false).
... to convert between javascript boolean values (jsval) and c boolean values, use jsval_to_boolean and boolean_to_jsval.

JSVAL_IS_VOID
determines if a given jsval is the javascript value undefined.
... syntax jsval_is_void(v) description jsval_is_void(v) is true if v is jsval_void, which represents the javascript value undefined.
...if (jsval_is_void(myitem)) { ...

JSVAL_ONE
the jsval that represents the javascript number 1.
... syntax jsval_one description jsval_one is equivalent to int_to_jsval(1).
... see also mxr id search for jsval_one int_to_jsval js_newcontext jsval_null jsval_void jsval_true jsval_false jsval_zero bug 1177825 -- removed ...

JSVAL_TO_DOUBLE
casts a given jsval to a jsdouble without any type checking or error handling.
... syntax jsdouble jsval_to_double(jsval v); description jsval_to_double casts a specified js value, v, to a c floating-point number of type jsdouble.
... as a precondition, jsval_is_double(v) must be true.

JSVAL_TO_STRING
cast a jsval to type jsstring * without a type check.
... syntax jsstring * jsval_to_string(jsval v); description jsval_to_string casts the argument, v, to type jsstring *.
... as a precondition, jsval_is_string(v) must be true.

JSVAL_VOID
the jsval that represents the javascript value undefined.
... syntax jsval_void description jsval_void is a jsval constant that represents the javascript value undefined.
... see also mxr id search for jsval_void jsval_null jsval_true jsval_false jsval_zero jsval_one bug 1177825 -- removed ...

JSVAL_ZERO
the jsval that represents the javascript number 0.
... syntax jsval_zero description jsval_zero is equivalent to int_to_jsval(0).
... see also mxr id search for jsval_zero int_to_jsval js_newcontext jsval_null jsval_void jsval_true jsval_false jsval_one bug 1177825 -- removed ...

PRIVATE_TO_JSVAL
cast raw void * pointers to type jsval and vice versa.
... syntax jsval private_to_jsval(void *ptr); void * jsval_to_private(jsval v); // obsoleted since jsapi 32 description with private_to_jsval(), an application can store a private data pointer, p, as a jsval.
... see also mxr id search for private_to_jsval js::privatevalue bug 952650 bug 1177892 -- removed ...

STRING_TO_JSVAL
syntax jsval string_to_jsval(jsstring *str) name type description obj jsstring * a pointer to a js string to convert to a jsval.
... description string_to_jsval casts a given jsstring * to jsval.
... see also mxr id search for string_to_jsval js::stringvalue bug 1177892 -- removed ...

JSVAL_IS_GCTHING
syntax jsval_is_gcthing(v) description jsval_is_gcthing(v) is true if the jsval v is either jsval_null or a reference to a value that is subject to garbage collection.
...see jsval for alternatives.

JSVAL_IS_PRIMITIVE
determine if a given jsval is of a primitive type.
... syntax jsval_is_primitive(v) description jsval_is_primitive(v) is true if v is undefined, null, a boolean, a number, or a string.

Index
17 jsapi reference needscontent, spidermonkey js::deflatestringtoutf8buffer 18 boolean_to_jsval jsapi reference, obsolete, spidermonkey boolean_to_jsval converts a bool argument, b, to a boolean jsval.
... 19 double_to_jsval jsapi reference, obsolete, spidermonkey double_to_jsval is the inverse of js::tonumber.
... 20 int_fits_in_jsval jsapi reference, obsolete, spidermonkey determines if a specified c integer value, i, lies within the range allowed for integer jsvals.
...And 48 more matches

SpiderMonkey 1.8.5
getters and setters of type jspropertyop took an id parameter of type jsval.
...instead use double_to_jsval, int_to_jsval, and uint_to_jsval, which are faster and can't fail.
... since jsdoubles are now stored in the jsval, instead of on the heap, we no longer need to define roots for them.
...And 18 more matches

nsIXPConnect
sourcetext); void debugdumpjsstack(in prbool showargs, in prbool showlocals, in prbool showthisprops); void debugdumpobject(in nsisupports acomobj, in short depth); [noscript,notxpcom] prbool definedomquickstubs(in jscontextptr cx, in jsobjectptr proto, in pruint32 flags, in pruint32 interfacecount, [array, size_is(interfacecount)] in nsiidptr interfacearray); jsval evalinsandboxobject(in astring source, in jscontextptr cx, in nsixpconnectjsobjectholder sandbox, in prbool returnstringonly); native code only!
... void flagsystemfilenameprefix(in string afilenameprefix, in prbool awantnativewrappers); void garbagecollect(); [noscript,notxpcom] void getcaller(out jscontextptr ajscontext, out jsobjectptr aobject); jsval getcowforobject(in jscontextptr ajscontext, in jsobjectptr aparent, in jsobjectptr awrappedobj); native code only!
...pednative getwrappednativeofjsobject(in jscontextptr ajscontext, in jsobjectptr ajsobj); nsixpconnectwrappednative getwrappednativeofnativeobject(in jscontextptr ajscontext, in jsobjectptr ascope, in nsisupports acomobj, in nsiidref aiid); nsixpconnectjsobjectholder getwrappednativeprototype(in jscontextptr ajscontext, in jsobjectptr ascope, in nsiclassinfo aclassinfo); jsval getwrapperforobject(in jscontextptr ajscontext, in jsobjectptr aobject, in jsobjectptr ascope, in nsiprincipal aprincipal, in unsigned long afilenameflags); native code only!
...And 18 more matches

SpiderMonkey 1.8.7
since jsdoubles are now stored in the jsval, instead of on the heap, we no longer need to define roots for them.
...type changes jsval the base data type, jsval, which represents all possible values in javascript, has changed from 32- to 64-bits wide, and the underlying representation has changed from a c integer type to a c struct.
... this change to a struct means that certain tricks, such as writing switch statements in c with jsval cases are no longer legal.
...And 16 more matches

nsIXPCScriptable
ecreate(in nsisupports nativeobj, in jscontextptr cx, in jsobjectptr globalobj, out jsobjectptr parentobj); void create(in nsixpconnectwrappednative wrapper, in jscontextptr cx, in jsobjectptr obj); void postcreate(in nsixpconnectwrappednative wrapper, in jscontextptr cx, in jsobjectptr obj); prbool addproperty(in nsixpconnectwrappednative wrapper, in jscontextptr cx, in jsobjectptr obj, in jsval id, in jsvalptr vp); prbool delproperty(in nsixpconnectwrappednative wrapper, in jscontextptr cx, in jsobjectptr obj, in jsval id, in jsvalptr vp); prbool getproperty(in nsixpconnectwrappednative wrapper, in jscontextptr cx, in jsobjectptr obj, in jsval id, in jsvalptr vp); prbool setproperty(in nsixpconnectwrappednative wrapper, in jscontextptr cx, in jsobjectptr obj, in jsval id, in jsval...
...ptr vp); prbool enumerate(in nsixpconnectwrappednative wrapper, in jscontextptr cx, in jsobjectptr obj); prbool newenumerate(in nsixpconnectwrappednative wrapper, in jscontextptr cx, in jsobjectptr obj, in pruint32 enum_op, in jsvalptr statep, out jsid idp); prbool newresolve(in nsixpconnectwrappednative wrapper, in jscontextptr cx, in jsobjectptr obj, in jsval id, in pruint32 flags, out jsobjectptr objp); prbool convert(in nsixpconnectwrappednative wrapper, in jscontextptr cx, in jsobjectptr obj, in pruint32 type, in jsvalptr vp); void finalize(in nsixpconnectwrappednative wrapper, in jscontextptr cx, in jsobjectptr obj); prbool checkaccess(in nsixpconnectwrappednative wrapper, in jscontextptr cx, in jsobjectptr obj, in jsval id, in pruint32 mode, in jsvalptr vp); prbool call(in ...
...nsixpconnectwrappednative wrapper, in jscontextptr cx, in jsobjectptr obj, in pruint32 argc, in jsvalptr argv, in jsvalptr vp); prbool construct(in nsixpconnectwrappednative wrapper, in jscontextptr cx, in jsobjectptr obj, in pruint32 argc, in jsvalptr argv, in jsvalptr vp); prbool hasinstance(in nsixpconnectwrappednative wrapper, in jscontextptr cx, in jsobjectptr obj, in jsval val, out prbool bp); void trace(in nsixpconnectwrappednative wrapper, in jstracerptr trc, in jsobjectptr obj); prbool equality(in nsixpconnectwrappednative wrapper, in jscontextptr cx, in jsobjectptr obj, in jsval val); jsobjectptr outerobject(in nsixpconnectwrappednative wrapper, in jscontextptr cx, in jsobjectptr obj); jsobjectptr innerobject(in nsixpconnectwrappednative wrapper, in jscontextptr cx, in jso...
...And 14 more matches

nsIJSON
1.0 66 introduced gecko 1.9 inherits from: nsisupports last changed in gecko 7.0 (firefox 7.0 / thunderbird 7.0 / seamonkey 2.4) note: this interface may only be used from javascript code, with the exception of the legacydecodetojsval() method.
... jsobject decode(in astring str); obsolete since gecko 7.0 jsval decodetojsval(in astring str, in jscontext cx); native code only!
... jsobject decodefromstream(in nsiinputstream stream, in long contentlength); astring encode(in jsobject value); obsolete since gecko 7.0 astring encodefromjsval(in jsvaljsval value, in jscontext cx); native code only!
...And 12 more matches

Mozilla DOM Hacking Guide
a function for example can be represented by a jsfunction, a jsobject, a jsval, ...
... static print32 getarrayindexfromid(jscontext *cx, jsval id, prbool *aisnumber = nsnull): if the js value is an integer, then *aisnumber is true, and the integer is returned.
... static inline prbool isreadonlyreplaceable(jsval id) { ...
...And 6 more matches

JSAPI User Guide
the arguments do not have native c++ types like int and float; rather, they are jsvals, javascript values.
...the jsapi provides a data type, js::value (also with a deprecated jsval typedef), which can contain javascript values of any type.
... for integers and boolean values, a jsval contains the value itself.
...And 6 more matches

JS_PushArguments
convert any number of arguments to jsvals and store the resulting jsvals in an array.
... syntax jsval * js_pusharguments(jscontext *cx, void **markp, const char *format, ...); jsval * js_pushargumentsva(jscontext *cx, void **markp, const char *format, va_list ap); name type description cx jscontext * the context in which to perform any necessary conversions.
... various (in js_pusharguments) a variable number of arguments to be converted to jsvals.
...And 6 more matches

JSAPI reference
ption js_throwstopiteration added in spidermonkey 1.8 js_isstopiteration added in spidermonkey 31 typedef jsexceptionstate js_saveexceptionstate js_restoreexceptionstate js_dropexceptionstate these functions translate errors into exceptions and vice versa: js_reportpendingexception js_errorfromexception js_throwreportederror obsolete since jsapi 29 values and types typedef jsval js::value js::value constructors: js::nullvalue added in spidermonkey 24 js::undefinedvalue added in spidermonkey 24 js::booleanvalue added in spidermonkey 24 js::truevalue added in spidermonkey 24 js::falsevalue added in spidermonkey 24 js::numbervalue added in spidermonkey 24 js::int32value added in spidermonkey 24 js::doublevalue added in spidermonkey 24 js::float32value added ...
...onkey 24 js::stringvalue added in spidermonkey 24 js::objectvalue added in spidermonkey 24 js::objectornullvalue added in spidermonkey 24 js::symbolvalue added in spidermonkey 38 js::value constants: js::nullhandlevalue added in spidermonkey 24 js::undefinedhandlevalue added in spidermonkey 24 js::truehandlevalue added in spidermonkey 38 js::falsehandlevalue added in spidermonkey 38 jsval constants: jsval_null obsolete since jsapi 42 jsval_void obsolete since jsapi 42 jsval_true obsolete since jsapi 42 jsval_false obsolete since jsapi 42 jsval_zero obsolete since jsapi 42 jsval_one obsolete since jsapi 42 function and macros for checking the type of a jsval: enum jstype js_typeofvalue all of the following are deprecated.
... jsval_is_null obsolete since jsapi 32 jsval_is_void obsolete since jsapi 32 jsval_is_boolean obsolete since jsapi 32 jsval_is_number obsolete since jsapi 32 jsval_is_int obsolete since jsapi 32 jsval_is_double obsolete since jsapi 32 jsval_is_string obsolete since jsapi 32 jsval_is_object obsolete since jsapi 15 jsval_is_primitive obsolete since jsapi 32 jsval_is_gcthing obsolete since jsapi 32 high-level type-conversion routines for packing and unpacking function arguments.
...And 5 more matches

nsITelemetry
1.0 66 introduced gecko 6.0 inherits from: nsisupports last changed in gecko 7.0 (firefox 7.0 / thunderbird 7.0 / seamonkey 2.4) implemented by: @mozilla.org/base/telemetry;1 as a service: let telemetry = components.classes["@mozilla.org/base/telemetry;1"] .getservice(components.interfaces.nsitelemetry); method overview jsval gethistogrambyid(in acstring id); jsval snapshothistograms(in uint32_t adataset, in boolean asubsession, in boolean aclear); jsval getkeyedhistogrambyid(in acstring id); void capturestack(in acstring name); jsval snapshotcapturedstacks([optional] in boolean clear); nsisupports getloadedmodules(); jsval snapshotkeyedhistograms(in uint32_t ada...
...taset, in boolean asubsession, in boolean aclear); void sethistogramrecordingenabled(in acstring id, in boolean enabled); void asyncfetchtelemetrydata(in nsifetchtelemetrydatacallback acallback); double mssinceprocessstart(); void scalaradd(in acstring aname, in jsval avalue); void scalarset(in acstring aname, in jsval avalue); void scalarsetmaximum(in acstring aname, in jsval avalue); jsval snapshotscalars(in uint32_t adataset, [optional] in boolean aclear); void keyedscalaradd(in acstring aname, in astring akey, in jsval avalue); void keyedscalarset(in acstring aname, in astring akey, in jsval avalue); void keyedscalarsetmaximum(in acstring aname, in astring akey, in jsval avalue); jsval snaps...
...hotkeyedscalars(in uint32_t adataset, [optional] in boolean aclear); void clearscalars(); test only void flushbatchedchildtelemetry(); void recordevent(in acstring acategory, in acstring amethod, in acstring aobject, [optional] in jsval avalue, [optional] in jsval extra); void seteventrecordingenabled(in acstring acategory, in boolean aenabled); jsval snapshotevents(in uint32_t adataset, [optional] in boolean aclear); void registerevents(in acstring acategory, in jsval aeventdata); void registerscalars(in acstring acategoryname, in jsval ascalardata); void clearevents(); test only attributes attribute type description canrecordbase boolean a flag indicating if telemetry can record base...
...And 5 more matches

JS::Value
the now-deprecated jsval methods allowed jsval_to_object(val) when jsval_is_null(val), but this was a source of constant bugs.
... the jsval typedef for js::value js::value was historically known in the jsapi as jsval.
... spidermonkey 1.8.5 made jsval into a c struct and exposed it in c++ through the full-fledged js::value class.
...And 4 more matches

JS_NewDoubleValue
create a floating-point jsval syntax jsbool js_newdoublevalue(jscontext *cx, jsdouble d, jsval *rval); name type description cx jscontext * the context in which to create the new number.
...this must not be a value that could fit in an integer jsval (see int_fits_in_jsval).
... rval jsval * out parameter.
...And 4 more matches

JS_NewNumberValue
use js_numbervalue instead convert a c floating-point number of type jsdouble to a jsval.
... syntax jsbool js_newnumbervalue(jscontext *cx, jsdouble d, jsval *rval); name type description cx jscontext * the context in which to create the new number.
... rval jsval * out parameter.
...And 4 more matches

JSFastNative
syntax typedef jsbool (*jsfastnative)(jscontext *cx, unsigned int argc, jsval *vp); name type description cx jscontext * the context in which the fast native is being called.
... vp jsval * the arguments, including the this argument, the return-value slot, and the callee function object are accessible through this pointer using macros described below.
... description the callback should use the following macros to access the fields of vp: macro name description js_callee(cx, vp) returns the function object that was called, as a jsval.
...And 3 more matches

JS_ConvertArguments
syntax bool js_convertarguments(jscontext *cx, const js::callargs &args, const char *format, ...); // added in spidermonkey 31 bool js_convertarguments(jscontext *cx, unsigned argc, jsval *argv, const char *format, ...); // obsolete since jsapi 30 name type description cx jscontext * the context in which to perform any necessary conversions.
...obsolete since jsapi 30 argv jsval * pointer to the vector of arguments to convert.
...(if conversion creates a new gc thing, the corresponding jsval is written back to argv, which is rooted.) description js_convertarguments provides a convenient way to translate a series of js values into their corresponding js types with a single function call.
...And 3 more matches

JSAPI Cookbook
sobject *global, const char *message, const char *filename, int32 lineno) { jsstring *messagestr; jsstring *filenamestr; js::value args[3]; js::value exc; messagestr = js_newstringcopyz(cx, message); if (!messagestr) return false; filenamestr = js_newstringcopyz(cx, filename); if (!filenamestr) return false; args[0] = string_to_jsval(messagestr); args[1] = string_to_jsval(filenamestr); args[2] = int_to_jsval(lineno); if (js_callfunctionname(cx, global, "error", 3, args, &exc)) js_setpendingexception(cx, exc); return false; } ...
...use jsval_to_object to cast y to type jsobject *.
... /* jsapi */ if (!js_defineproperty(cx, obj, "prop", int_to_jsval(123), js_propertystub, js_strictpropertystub, jsprop_readonly | jsprop_enumerate | jsprop_permanent)) { return false; } defining a property with a getter and setter object.defineproperty() can be used to define properties in terms of two accessor functions.
...And 2 more matches

JS_AddArgumentFormatter
callback syntax jsbool (*jsargumentformatter)(jscontext *cx, const char *format, jsbool fromjs, jsval **vpp, va_list *app); name type description cx jscontext * the context in which the conversion is being performed.
... fromjs jsbool js_true if the conversion function should convert from jsval values to c values; js_false if the conversion function should convert from c values to jsval values.
... vpp jsval ** in-out parameter.
...And 2 more matches

JS_DefinePropertyWithTinyId
syntax jsbool js_definepropertywithtinyid( jscontext *cx, jsobject *obj, const char *name, int8 tinyid, jsval value, jspropertyop getter, jspropertyop setter, unsigned int attrs); jsbool js_defineucpropertywithtinyid( jscontext *cx, jsobject *obj, const jschar *name, size_t namelen, int8 tinyid, jsval value, jspropertyop getter, jspropertyop setter, unsigned int attrs); name type description cx jscontext * the context in which to define the property.
... value jsval initial stored value for the new property.
...any time the javascript engine would pass the name of the property as a string to the id parameter of a tiny-id-aware callback, it passes int_to_jsval(tinyid) instead.
...And 2 more matches

nsIDispatchSupport
inherits from: nsisupports last changed in gecko 1.7 method overview void comvariant2jsval(in comvariantptr comvar, out jsval val); unsigned long gethostingflags(in string acontext); boolean isclassmarkedsafeforscripting(in nscidref cid, out boolean classexists); boolean isclasssafetohost(in jscontextptr cx, in nscidref cid, in boolean capscheck, out boolean classexists); boolean isobjectsafeforscripting(in voidptr theobject, in nsiidref id); void jsval2comvariant(in jsval var, out comvariant comvar); methods comvariant2jsval() converts a com variant to a jsval.
... void comvariant2jsval( in comvariantptr comvar, out jsval val ); parameters comvar the com variant to be converted.
... val the jsval to receive the converted value.
...And 2 more matches

nsIJetpack
1.0 66 introduced gecko 2.0 inherits from: nsisupports last changed in gecko 2.0 (firefox 4 / thunderbird 3.3 / seamonkey 2.1) method overview void sendmessage(in astring amessagename /* [optional] in jsval v1, [optional] in jsval v2, ...
... */); void registerreceiver(in astring amessagename, in jsval areceiver); void unregisterreceiver(in astring amessagename, in jsval areceiver); void unregisterreceivers(in astring amessagename); void evalscript(in astring ascript); nsivariant createhandle(); void destroy(); methods sendmessage() this method asynchronously sends a message to the jetpack process.
... void sendmessage( in astring amessagename, [optional] in jsval v1, optional [optional] in jsval v2, optional ...
...And 2 more matches

XPIDL
ject should only be used with methods that act like queryinterface autf8string const nsacstring& nsacstring& string full unicode set permitted (translated to utf-8) acstring const nsacstring& nsacstring& string only chars in range \u0000-\u00ff permitted astring const nsastring& nsastring& string full unicode set permitted jsval const jsval& jsval* anything jsid jsid jsid* not allowed promise mozilla::dom::promise* mozilla::dom::promise** promise typedefs in idl are basically as they are in c or c++: you define first the type that you want to refer to and then the name of the type.
... jsval this type gets const when an in type.
...however, scriptable methods must contain parameters and a return type that can be translated to script: any native type, save those declared with an nsid, utf8string, cstring, astring, or jsval property, may not be used in a scriptable method or attribute.
...And 2 more matches

JSCheckAccessOp
(it is also the type of the callback set by js_setcheckobjectaccesscallback.) syntax typedef jsbool (* jscheckaccessop)(jscontext *cx, jsobject *obj, jsval id, jsaccessmode mode, jsval *vp); name type description cx jscontext * the js context in which the property access attempt is occurring.
... id jsval the name or index of the property being accessed.
... vp jsval * out parameter.
...as for jspropertyop, id is either a string or an int jsval.

JSNewEnumerateOp
(you can use private_to_jsval to tag the pointer to be stored).
... the number of properties that will be enumerated should be returned as an integer jsval in *idp, if idp is non-null, and provided the number of enumerable properties is known.
... if idp is non-null and the number of enumerable properties can't be computed in advance, *idp should be set to jsval_zero.
...the opaque iterator state pointed at by statep is destroyed and *statep is set to jsval_null if there are no properties left to enumerate.

JS_Add*Root
syntax jsbool js_addvalueroot(jscontext *cx, jsval *vp); jsbool js_addstringroot(jscontext *cx, jsstring **spp); jsbool js_addobjectroot(jscontext *cx, jsobject **opp); jsbool js_addgcthingroot(jscontext *cx, void **rp); jsbool js_addnamedvalueroot(jscontext *cx, jsval *vp, const char *name); jsbool js_addnamedstringroot(jscontext *cx, jsstring **spp, const char *name); jsbool js_addnamedobjectroot(jscontext *cx, jsobject **opp, const char *name...
... vp jsval * (in js_addvalueroot and js_addnamedvalueroot) the address of the jsval variable to root spp jsstring ** (in js_addstringroot and js_addnamedstringroot) the address of the jsstring* variable to root opp jsobject ** (in js_addobjectroot and js_addnamedobjectroot) the address of the jsobject* variable to root rp void ** (in js_addgcthingroot and js_addnamedgcthingroot) the address of the jsstring* or jsobject* (not jsval) variable to root n...
... vp/spp/opp/rp is the address of a c/c++ variable (or field, or array element) of type jsstring *, jsobject *, or jsval.
... a jsval is not a gc-thing (it has tag bits and may be a different size altogether) and thus the address of a jsval variable must not be passed to js_addgcthingroot.

JS_NewObjectForConstructor
syntax jsobject * js_newobjectforconstructor(jscontext *cx, const jsclass *clasp, const js::callargs& args); // added in jsapi 32 jsobject * js_newobjectforconstructor(jscontext *cx, jsclass *clasp, const jsval *vp); // added in jsapi 14, obsolete since jsapi 32 jsobject * js_newobjectforconstructor(jscontext *cx, const jsval *vp); // obsolete since jsapi 14 name type description cx jscontext * the context in which to create the new object.
...added in spidermonkey 17 vp jsval * pointer to a constructor.
...if the constructor argument is not an object jsval, this function will assert (in debug builds).
... see also mxr id search for js_newobjectforconstructor js_newobject object_to_jsval bug 581263 - added bug 738075 - added clasp parameter bug 959787 - added args parameter ...

JS_SameValue
this article covers features introduced in spidermonkey 1.8.1 determines if two jsvals are the same, as determined by the samevalue algorithm in ecmascript 262, 5th edition.
...t to the following javascript: function samevalue(v1, v2) { if (v1 === 0 && v2 === 0) return 1 / v1 === 1 / v2; if (v1 !== v1 && v2 !== v2) return true; return v1 === v2; } syntax // added in spidermonkey 45 bool js_samevalue(jscontext *cx, js::handle<js::value> v1, js::handle<js::value> v2, bool *same); // obsolete since jsapi 39 bool js_samevalue(jscontext *cx, jsval v1, jsval v2, bool *same); name type description cx jscontext * pointer to a js context from which to derive runtime information.
... v1 js::handle&lt;js::value&gt; / jsval the first value.
... v2 js::handle&lt;js::value&gt; / jsval the second value.

nsIXPCException
inherits from: nsiexception last changed in gecko 1.9.2 (firefox 3.6 / thunderbird 3.1 / fennec 1.0) method overview void initialize(in string amessage, in nsresult aresult, in string aname, in nsistackframe alocation, in nsisupports adata, in nsiexception ainner); xpcexjsval stealjsval(); native code only!
... void stowjsval(in xpcexjscontextptr cx, in xpcexjsval val); native code only!
... methods initialize() void initialize( in string amessage, in nsresult aresult, in string aname, in nsistackframe alocation, in nsisupports adata, in nsiexception ainner ); parameters amessage aresult aname alocation adata ainner native code only!stealjsval xpcexjsval stealjsval(); parameters none.
... return value native code only!stowjsval void stowjsval( in xpcexjscontextptr cx, in xpcexjsval val ); parameters cx val remarks components.exception is a javascript constructor to create nsixpcexception objects.

64-bit Compatibility
the following types or typedefs are always 64-bit on 64-bit platforms, and 32-bit on 32-bit platforms: pointers uintptr_t, intptr_t, ptrdiff_t, (probably) size_t jsval jsuword, jsword length of a string, though the actual length cannot exceed 30 bits jsuintptr, jsintptr, jsptrdiff, jsuptrdiff, jssize, jsuword, jsword (let's not use these, kthx) the following types are 32-bit on 32-bit platforms.
... remember to use argsize_p where appropriate - on pointers or natively sized integers (including jsvals).
... stobj_get_fslot - returns jsval-width lins stobj_get_dslot - returns jsval-width lins stobj_set_dslot - stores jsval-width lins stobj_set_fslot - stores jsval-width lins box_jsval - returns jsval-width lins unbox_jsval - expects jsval-width lins ...

JSObjectOps.getProperty
syntax typedef jsbool (*jspropertyidop)( jscontext *cx, jsobject *obj, jsid id, jsval *vp); name type description cx jscontext * pointer to the js context in which the property access is happening.
... vp jsval * in/out parameter.
... if deleting without error, *vp will be jsval_false if obj[id] is permanent, and jsval_true if id named a direct property of obj that was in fact deleted, or if id names no direct property of obj (id could name a property of a prototype, or no property in obj or its prototype chain).

JS_ConstructObject
syntax jsobject * js_constructobject(jscontext *cx, jsclass *clasp, jsobject *proto, jsobject *parent); jsobject * js_constructobjectwitharguments(jscontext *cx, jsclass *clasp, jsobject *proto, jsobject *parent, unsigned int argc, jsval *argv); name type description cx jscontext * the context in which to create the new object.
... argv jsval * (only in js_constructobjectwitharguments) the array of arguments to pass to the constructor.
...otherwise, the first argc elements of this array must be populated with valid jsval values.

JS_EvaluateScriptForPrincipals
syntax jsbool js_evaluatescriptforprincipals(jscontext *cx, jsobject *obj, jsprincipals *principals, const char *src, unsigned int length, const char *filename, unsigned int lineno, jsval *rval); jsbool js_evaluatescriptucforprincipals(jscontext *cx, jsobject *obj, jsprincipals *principals, const jschar *src, unsigned int length, const char *filename, unsigned int lineno, jsval *rval); jsbool js_evaluatescriptforprincipalsversion(jscontext *cx, jsobject *obj, jsprincipals *principals, const char *bytes, unsigned int length, const char *filename, unsigned int line...
...no, jsval *rval, jsversion version); jsbool js_evaluateucscriptforprincipalsversion(jscontext *cx, jsobject *obj, jsprincipals *principals, const jschar *chars, unsigned int length, const char *filename, unsigned int lineno, jsval *rval, jsversion version); name type description cx jscontext * the context in which to run the script.
... rval jsval * out parameter.

JS_GetInstancePrivate
syntax void * js_getinstanceprivate(jscontext *cx, js::handle<jsobject*> obj, const jsclass *clasp, js::callargs *args); // added in jsapi 32 void * js_getinstanceprivate(jscontext *cx, js::handle<jsobject*> obj, const jsclass *clasp, jsval *argv); // obsolete since jsapi 32 name type description cx jscontext * a context.
...added in spidermonkey 32 argv jsval * optional argument vector, used for error reporting.
...see also mxr id search for js_getinstanceprivate jsclass_has_private jsval_to_private js_getprivate js_initclass js_instanceof js_reporterror js_setprivate bug 959787 -- added args parameter ...

JS_IsConstructing_PossiblyWithGivenThisObject
syntax static jsbool js_isconstructing_possiblywithgiventhisobject(jscontext *cx, const jsval *vp, jsobject **maybethis); name type description cx jscontext * the context.
... vp const jsval * maybethis jsobject ** description in the case of a constructor called from js_constructobject and js_initclass where the class has the jsclass_construct_prototype flag set, spidermonkey passes the constructor a non-standard this object.
... jsbool foo_native(jscontext *cx, unsigned int argc, jsval *vp) { jsobject *maybethis; if (js_isconstructing_possiblywithgiventhisobject(cx, vp, &maybethis)) { // native called as a constructor if (maybethis) // native called as a constructor with maybethis as 'this' } else { // native called as function, maybethis is still uninitialized } } note: a spidermonkey embedding does not need to use this query unless the embedding uses js_constructobject(), js_initclass() and jsclass_construct_prototype as described above.

JS_NewArrayObject
syntax jsobject * js_newarrayobject(jscontext *cx, const js::handlevaluearray& contents); // added in spidermonkey 31 jsobject * js_newarrayobject(jscontext *cx, size_t length); // added in spidermonkey 31 jsobject * js_newarrayobject(jscontext *cx, int length, jsval *vector); // obsolete since jsapi 30 name type description cx jscontext * the context in which to create the new array.
... vector jsval * pointer to the initial values for the array's elements, or null.
...this avoids unrooted jsvals in vector from being subject to garbage collection until the new object has been populated.

JS_StrictlyEqual
syntax // added in spidermonkey 45 bool js_strictlyequal(jscontext *cx, js::handle<js::value> v1, js::handle<js::value> v2, bool *equal); // obsolete since jsapi 39 bool js_strictlyequal(jscontext *cx, jsval v1, jsval v2, bool *equal); name type description cx jscontext * the context in which to perform the conversion.
... v1, v2 js::handle&lt;js::value&gt; / jsval the value to compare.
... comparing jsvals directly in c++, as in v1 == v2, does not produce a meaningful result, since it is possible for two distinct jsstrings or jsdoubles to represent the same string or number.

JS_ValueToString
convert a jsval to a jsstring.
... syntax jsstring * js_valuetostring(jscontext *cx, jsval v); name type description cx jscontext * the context in which to perform the conversion.
... v jsval the value to convert.

mozIJSSubScriptLoader
method overview jsval loadsubscript(in string url, in object targetobj optional, in string charset optional); jsval loadsubscriptwithoptions(in string url, in object options); methods loadsubscript() synchronously loads and executes the script from the specified url.
... jsval loadsubscript( in string url, in object targetobj optional, in string charset optional, ); example let context = {}; services.scriptloader.loadsubscript("chrome://my-package/content/foo-script.js", context, "utf-8" /* the script's encoding */); parameters url the url pointing to the script to load.
... jsval loadsubscriptwithoptions( in string url, in object options ); parameters url the url pointing to the script to load.

nsIBlocklistService
1.0 66 introduced gecko 1.9 inherits from: nsisupports last changed in gecko 29 (firefox 29 / thunderbird 29 / seamonkey 2.26) method overview unsigned long getaddonblockliststate(in jsval addon, [optional] in astring appversion, [optional] in astring toolkitversion); unsigned long getpluginblockliststate(in nsiplugintag plugin, [optional] in astring appversion, [optional] in astring toolkitversion); boolean isaddonblocklisted(in jsval addon, [optional] in astring appversion, [optional] in astring toolkitversion); constants constant value description state_not_blocked 0 state_softblocked 1 ...
...unsigned long getaddonblockliststate( in jsval addon, in astring appversion, optional in astring toolkitversion optional ); parameters addon the addon object whose blocklist state is to be determined.
...boolean isaddonblocklisted( in jsval addon, in astring appversion, optional from gecko 1.9.1 in astring toolkitversion optional from gecko 1.9.1 ); parameters addon the addon object to be checked.

nsIDOMMozNetworkStatsManager
you can test for the presence of the service as follows, for example: if ("moznetworkstats" in navigator) { /* networkstats is available */ } else { alert("i'm sorry, but networkstats services are not supported."); } method overview nsidomdomrequest getsamples(in nsisupports network, in jsval start, in jsval end, [optional] in jsval options /* networkstatsgetoptions */); nsidomdomrequest addalarm(in nsisupports network, in long threshold, [optional] in jsval options /* networkstatsalarmoptions */); nsidomdomrequest getallalarms([optional] in nsi...
... nsidomdomrequest getsamples(in nsisupports network, in jsval start, in jsval end, [optional] in jsval options /* networkstatsgetoptions */); parameters network the origin of the data.
... nsidomdomrequest addalarm(in nsisupports network, in long threshold, [optional] in jsval options /* networkstatsalarmoptions */); parameters network the origin of the data.

JS::PerfMeasurement
perfmeasurement* js::extractperfmeasurement(jsval wrapper) if you are the c++ side of an xpcom interface, and you want to benchmark only part of your execution time but make the results available to javascript, you can declare a bare jsval argument in your .idl file and have javascript pass a perfmeasurement object that it created in that argument slot.
... the jsval you receive points to a javascript wrapper object.

How to embed the JavaScript engine
static bool doit(jscontext *cx, unsigned argc, jsval *vp) { js::callargs args = callargsfromvp(argc, vp); /* * look in argv for argc actual parameters, set *rval to return a * value to the caller.
...// js::autovaluevector argv(cx); // argv.resize(2); js::autovaluearray<2> argv(cx); argv[0].setint32(1); argv[1].setint32(2); then call the function: // [spidermonkey 24] pass arguments length and the 'jsval *' pointer.

JSBool
these values must not be used as jsvals.
... instead, use jsval_true and jsval_false, and use boolean_to_jsval and jsval_to_boolean to convert.

JSClass
, null, null, printer_finalize }; /* spidermonkey 31 or older * static jsclass printer_class = { * "printer", * jsclass_has_private, * js_propertystub, js_propertystub, js_propertystub, js_strictpropertystub, * js_enumeratestub, js_resolvestub, js_convertstub, printer_finalize, * jsclass_no_optional_members * }; */ bool printer_construct(jscontext *cx, unsigned argc, jsval *vp) { js::callargs args = js::callargsfromvp(argc, vp); jsobject *obj = js_newobjectforconstructor(cx, &printer_class, args); /* spidermonkey 31 or older * jsobject *obj = js_newobjectforconstructor(cx, &printer_class, vp); */ if (!obj) return false; myprinter *p = new myprinter; if (p == null) { js_reportoutofmemory(cx); return false; ...
... } js_setprivate(cx, obj, p); args.rval().setobject(*obj); /* spidermonkey 31 or older * js_set_rval(cx, vp, object_to_jsval(obj)); */ return true; } { js_initclass(cx, global, js::null(), &printer_class, printer_construct, 1, null, null, null, null); } see also mxr id search for jsclass jsclass.flags js_getclass js_initclass js_newobject js_newobjectforconstructor js_instanceof bug 638291 - added trace bug 702507 - removed jsclass_construct_prototype bug 726944 - removed xdrobject, reserved0 and reserved1 bug 886829 - made finalize optional bug 957688 - removed checkaccess bug 1103368 - made most of members optional bug 1097267 - removed jsclass_new_enumerate bug 1054756 - removed convert bug 1261723 - class ops are moved to a ...

JSObjectOps.defaultValue
syntax typedef jsbool (*jsconvertop)(jscontext *cx, jsobject *obj, jstype type, jsval *vp); name type description cx jscontext * pointer to the js context in which the conversion is needed.
... vp jsval * out parameter.

JSObjectOps.defineProperty
syntax jsbool (*jsdefinepropop)(jscontext *cx, jsobject *obj, jsid id, jsval value, jspropertyop getter, jspropertyop setter, unsigned int attrs); name type description cx jscontext * pointer to the js context in which the property is being defined.
... value jsval the initial value for the new property.

JSObjectOps.getRequiredSlot
syntax typedef jsval (*jsgetrequiredslotop)(jscontext *cx, jsobject *obj, uint32 slot); typedef jsbool (*jssetrequiredslotop)(jscontext *cx, jsobject *obj, uint32 slot, jsval v); name type description cx jscontext * the js context in which we access the slot.
... v jsval the value to store in the slot, for jssetrequiredslotop.

JS_CallFunction
t char *name, const js::handlevaluearray& args, js::mutablehandlevalue rval); bool js_callfunctionvalue(jscontext *cx, js::handleobject obj, js::handlevalue fval, const js::handlevaluearray& args, js::mutablehandlevalue rval); /* obsolete since jsapi 30 */ bool js_callfunction(jscontext *cx, jsobject *obj, jsfunction *fun, unsigned argc, jsval *argv, jsval *rval); bool js_callfunctionname(jscontext *cx, jsobject *obj, const char *name, unsigned argc, jsval *argv, jsval *rval); bool js_callfunctionvalue(jscontext *cx, jsobject *obj, jsval fval, unsigned argc, jsval *argv, jsval *rval); name type description cx jscontext * pointer to a js context from which to der...
...obsolete since jsapi 30 argv jsval * pointer to the array of argument values to pass to the function.

JS_CheckAccess
syntax jsbool js_checkaccess(jscontext *cx, jsobject *obj, jsid id, jsaccessmode mode, jsval *vp, unsigned int *attrsp); name type description cx jscontext * the context in which to perform the access check.
... mode jsaccessmode the type of access requested (read, write, etc.) vp jsval * out parameter.

JS_ConvertArgumentsVA
syntax bool js_convertargumentsva(jscontext *cx, const js::callargs &args, const char *format, va_list ap); bool js_convertargumentsva(jscontext *cx, unsigned argc, jsval *argv, const char *format, va_list ap); name type description cx jscontext * pointer to a js context from which to derive runtime information.
...obsolete since jsapi 30 argv jsval * pointer to the vector of arguments to convert.

JS_DefineElement
unsigned attrs, jsnative getter = nullptr, jsnative setter = nullptr); bool js_defineelement(jscontext *cx, js::handleobject obj, uint32_t index, double value, unsigned attrs, jsnative getter = nullptr, jsnative setter = nullptr); /* obsolete since jsapi 32 */ js_defineelement(jscontext *cx, jsobject *obj, uint32_t index, jsval value, jspropertyop getter, jsstrictpropertyop setter, unsigned attrs); name type description cx jscontext * the context in which to create the new property.
... value js::handlevalue or js::handleobject or js::handlestring or int32_t or uint32_t or double or jsval initial value to assign to the property.

JS_EnterLocalRootScope
for example: jsbool my_getproperty(jscontext *cx, jsobject *obj, jsval id, jsval *vp) { jsbool ok; if (!js_enterlocalrootscope(cx)) return js_false; // this function doesn't need to bother rooting any new objects, // strings, or doubles it creates using cx.
...to determine if a jsval points to a gc thing, use jsval_is_gcthing.

JS_EvaluateScript
syntax jsbool js_evaluatescript(jscontext *cx, jsobject *obj, const char *src, unsigned int length, const char *filename, unsigned int lineno, jsval *rval); jsbool js_evaluateucscript(jscontext *cx, jsobject *obj, const jschar *src, unsigned int length, const char *filename, unsigned int lineno, jsval *rval); name type description cx jscontext * the context in which to run the script.
... rval jsval * out parameter.

JS_ExecuteScriptPart
syntax typedef enum jsexecpart { jsexec_prolog, jsexec_main } jsexecpart; jsbool js_executescriptpart( jscontext *cx, jsobject *obj, jsscript *script, jsexecpart part, jsval *rval); name type description cx jscontext * the context in which to execute the script.
... rval jsval * out parameter.

JS_ExecuteScriptVersion
syntax jsbool js_executescriptversion(jscontext *cx, jsobject *obj, jsobject *scriptobj, jsval *rval, jsversion version); name type description cx jscontext * the context in which to execute the script.
... rval jsval * out parameter.

JS_GetEmptyStringValue
syntax // added in spidermonkey 42 js::value js_getemptystringvalue(jscontext *cx); // obsolete since spidermonkey 42 jsval js_getemptystringvalue(jscontext *cx); name type description cx jscontext * a context.
... see also mxr id search for js_getemptystringvalue bug 1184564 -- changed jsval to js::value ...

JS_GetNaNValue
syntax // added in spidermonkey 42 js::value js_getnanvalue(jscontext *cx); // obsolete since spidermonkey 42 jsval js_getnanvalue(jscontext *cx); name type description cx jscontext * a context.
... see also mxr id search for js_getnanvalue js_getnegativeinfinityvalue js_getpositiveinfinityvalue bug 1184564 -- changed jsval to js::value ...

JS_GetPositiveInfinityValue
syntax // added in spidermonkey 42 js::value js_getpositiveinfinityvalue(jscontext *cx); js::value js_getnegativeinfinityvalue(jscontext *cx); // obsolete since spidermonkey 42 jsval js_getpositiveinfinityvalue(jscontext *cx); jsval js_getnegativeinfinityvalue(jscontext *cx); name type description cx jscontext * a context.
... see also mxr id search for js_getpositiveinfinityvalue mxr id search for js_getnegativeinfinityvalue js_getnanvalue bug 1184564 -- changed jsval to js::value ...

JS_GetReservedSlot
syntax // added in spidermonkey 42 js::value js_getreservedslot(jsobject *obj, uint32_t index); void js_setreservedslot(jsobject *obj, uint32_t index, js::value v); // obsolete since spidermonkey 42 jsval js_getreservedslot(jsobject *obj, uint32_t index); void js_setreservedslot(jsobject *obj, uint32_t index, jsval v); name type description obj jsobject * an object that has reserved slots.
... see also mxr id search for js_getreservedslot mxr id search for js_setreservedslot bug 1184564 -- changed jsval to js::value ...

JS_InstanceOf
syntax bool js_instanceof(jscontext *cx, js::handle<jsobject*> obj, const jsclass *clasp, js::callargs *args); // added in spidermonkey 38 bool js_instanceof(jscontext *cx, js::handle<jsobject*> obj, const jsclass *clasp, jsval *argv); // obsolete since jsapi 32 name type description cx jscontext * pointer to a js context from which to derive runtime information.
...added in spidermonkey 38 argv jsval * optional argument vector.

JS_IsConstructing
syntax jsbool js_isconstructing(jscontext *cx, jsval *vp); name type description cx jscontext * the cx parameter passed to the jsnative.
... vp jsval * the vp parameter passed to the jsnative.

JS_IsStopIteration
syntax // added in spidermonkey 42 bool js_isstopiteration(js::value v); // obsolete since spidermonkey 42 bool js_isstopiteration(jsval v); name type description v js::value the value to check.
... see also mxr id search for js_isstopiteration js_throwstopiteration bug 918170 bug 1184564 -- changed jsval to js::value ...

JS_LeaveLocalRootScopeWithResult
syntax void js_leavelocalrootscopewithresult(jscontext *cx, jsval rval); name type description cx jscontext * pointer to the context.
... rval jsval the result value that should remain protected from garbage collection.

JS_New
syntax jsobject * js_new(jscontext *cx, js::handleobject ctor, const js::handlevaluearray& args); // added in jsapi 32 jsobject * js_new(jscontext *cx, jsobject *ctor, unsigned argc, jsval *argv); // obsolete since jsapi 32 name type description cx jscontext * the context in which to create the new object.
...obsolete since jsapi 32 argv jsval * pointer to the element 0 of an array of argument values to pass to the constructor.

JS_NewDouble
to convert a jsdouble to a jsval, use js_newnumbervalue instead.
... warning: the argument d must not be a value that could fit in an integer jsval.

JS_NumberValue
syntax // added in spidermonkey 42 js::value js_numbervalue(double d); // obsolete since spidermonkey 42 jsval js_numbervalue(double d); name type description d double the numeric value to convert.
... see also mxr id search for js_numbervalue bug 752223 bug 1184564 -- changed jsval to js::value ...

JS_ParseJSON
syntax jsbool js_parsejson(jscontext *cx, const jschar *chars, uint32 len, jsval *vp); jsbool js_parsejsonwithreviver(jscontext *cx, const jschar *chars, uint32 len, jsval reviver, jsval *vp); name type description cx jscontext * pointer to a js context.
... vp jsval * out parameter.

JS_Remove*Root
syntax jsbool js_removevalueroot(jscontext *cx, jsval *vp); jsbool js_removestringroot(jscontext *cx, jsstring **spp); jsbool js_removeobjectroot(jscontext *cx, jsobject **opp); jsbool js_removegcthingroot(jscontext *cx, void **rp); name type description cx jscontext * a context.
... vp jsval * address of the jsval variable to remove from the root set.

JS_RemoveRootRT
do not pass a pointer to a js double, string, or object -- you must pass a pointer to a pointer or a pointer to a jsval that's a gc thing.
...see also mxr id search for js_removeroot jsval_is_gcthing js_addroot js_addnamedroot js_addnamedrootrt js_dumpnamedroots, js_removeroot ...

JS_SetCallReturnValue2
syntax void js_setcallreturnvalue2(jscontext *cx, jsval v); name type description cx jscontext * the context in which the native function is running.
... v jsval the id of the property of the reference value to be returned from the native.

JS_ValueToBoolean
syntax jsbool js_valuetoboolean(jscontext *cx, jsval v, jsbool *bp); name type description cx jscontext * the context in which to perform the conversion.
... v jsval the value to convert.

JS_ValueToECMAInt32
syntax jsbool js_valuetoecmaint32(jscontext *cx, jsval v, int32 *ip); jsbool js_valuetoecmauint32(jscontext *cx, jsval v, uint32 *ip); jsbool js_valuetouint16(jscontext *cx, jsval v, uint16 *ip); name type description cx jscontext * the context in which to perform the conversion.
... v jsval the javascript value to convert.

JS_ValueToInt32
syntax jsbool js_valuetoint32(jscontext *cx, jsval v, int32 *ip); name type description cx jscontext * the context in which to perform the conversion.
... v jsval the value to convert.

JS_ValueToNumber
syntax jsbool js_valuetonumber(jscontext *cx, jsval v, jsdouble *dp); name type description cx jscontext * the context in which to perform the conversion.
... v jsval the value to convert.

SpiderMonkey 38
ug 1107639) js::removeobjectrootrt (bug 1107639) js::removescriptroot (bug 1107639) js::removescriptrootrt (bug 1107639) js::removestringroot (bug 1107639) js::removestringrootrt (bug 1107639) js::removevalueroot (bug 1107639) js::removevaluerootrt (bug 1107639) jsclass_new_enumerate (bug 1097267) jsclass_new_resolve (bug 993026) jsid_is_object (bug 915482) jsnewresolveop (bug 993026) jsval_is_boolean (bug 952650) jsval_is_double (bug 952650) jsval_is_gcthing (bug 952650) jsval_is_int (bug 952650) jsval_is_null (bug 952650) jsval_is_number (bug 952650) jsval_is_primitive (bug 952650) jsval_is_string (bug 952650) jsval_is_void (bug 952650) jsval_to_boolean (bug 952650) jsval_to_double (bug 952650) jsval_to_gcthing (bug 952650) jsval_to_int (bug 952650) jsval_to_object (b...
...ug 952650) jsval_to_private (bug 952650) jsval_to_string (bug 952650) js_clearnonglobalobject (bug 1043281) js_clonefunctionobject (bug 1089026) js_compilefunction (bug 1089026) js_compileucfunction (bug 1089026) js_convertarguments (bug 1125784) js_convertargumentsva (bug 1125784) js_convertstub (bug 1103152) js_defineownproperty (bug 1017323) js_deletepropertystub (bug 1103152) js_doubletoint32 (bug 1112774) js_doubletouint32 (bug 1112774) js_enumeratestub (bug 1103152) js_evaluatescript (bug 1100579) js_evaluateucscript (bug 1100579) js_executescriptversion (bug 1095660) js_getflatstringchars (bug 1037869) js_getfunctioncallback (bug 1103269) js_getinternedstringchars (bug 1037869) js_getinternedstringcharsandlength (bug 1037869) js_getstringcharsandlength (bug 1037869)...

Interfacing with the XPCOM cycle collector
this is the same as for the jsobject case, but using the ns_impl_cycle_collection_trace_jsval_member_callback macro: ns_impl_cycle_collection_trace_begin(nsfoo) ...
... ns_impl_cycle_collection_trace_jsval_member_callback(msomejsval).

mozIAsyncHistory
0 66 introduced gecko 24.0 inherits from: nsisupports last changed in gecko 24.0 (firefox 24.0 / thunderbird 24.0 / seamonkey 2.21) implemented by: @mozilla.org/browser/history;1 as a service: var asynchistory = components.classes["@mozilla.org/browser/history;1"] .getservice(components.interfaces.moziasynchistory); method overview void getplacesinfo(in jsval aplaceidentifiers, in mozivisitinfocallback acallback); void isurivisited(in nsiuri auri, in mozivisitedstatuscallback acallback); void updateplaces(in moziplaceinfo, [optional] in mozivisitinfocallback acallback); methods getplacesinfo() starts an asynchronous request to determine whether or not a given uri has been visited; you must implement a callback to receive the ...
...void getplacesinfo( in jsval aplaceidentifiers, in mozivisitinfocallback acallback ); parameters aplaceidentifiers the uri for which to determine the visited status.

nsIBinaryInputStream
inherits from: nsiinputstream last changed in gecko 1.7 method overview pruint8 read8(); pruint16 read16(); pruint32 read32(); pruint64 read64(); unsigned long readarraybuffer(in pruint32 alength, in jsval aarraybuffer); prbool readboolean(); void readbytearray(in pruint32 alength, [array, size_is(alength), retval] out pruint8 abytes); void readbytes(in pruint32 alength, [size_is(alength), retval] out string astring); acstring readcstring(); double readdouble(); float readfloat(); astring readstring(); void setinputstream(in ns...
... unsigned long readarraybuffer(in pruint32 alength, in jsval aarraybuffer); parameters alength the number of bytes that should be read.

nsICookieManager
it is implemented by the @mozilla.org/cookiemanager;1 component, but should generally be accessed via services.cookies method overview void remove(in autf8string ahost, in acstring aname, in autf8string apath, in boolean ablocked, in jsval aoriginattributes); void removeall(); attributes attribute type description enumerator nsisimpleenumerator called to enumerate through each cookie in the cookie list.
... void remove( in autf8string ahost, in acstring aname, in autf8string apath, in boolean ablocked, in jsval aoriginattributes ); parameters ahost the host or domain for which the cookie was set.

nsIDOMHTMLAudioElement
last changed in gecko 2.0 (firefox 4 / thunderbird 3.3 / seamonkey 2.1) inherits from: nsidomhtmlmediaelement method overview unsigned long long mozcurrentsampleoffset(); void mozsetup(in pruint32 channels, in pruint32 rate); [implicit_jscontext] unsigned long mozwriteaudio(in jsval data); methods mozcurrentsampleoffset() non-standard this feature is non-standard and is not on a standards track.
...unsigned long mozwriteaudio( in jsval data ); parameters data the samples to write into the audio stream, specified either as a javascript array or as a numeric typed array.

nsIPushMessage
method overview domstring text(); jsval json(); void binary([optional] out uint32_t datalen, [array, retval, size_is(datalen)] out uint8_t data); methods text() extracts the message data as a utf-8 text string.
... jsval json(); parameters none.

nsIRadioInterfaceLayer
processid); void setupdatacall(in long radiotech, in domstring apn, in domstring user, in domstring passwd, in long chappap, in domstring pdptype); void starttone(in domstring dtmfchar); void stoptone(); void unregistercallback(in nsiriltelephonycallback callback); void unregisterdatacallcallback(in nsirildatacallback callback); attributes attribute type description currentstate jsval read only.
... obsolete since gecko 13.0 microphonemuted bool radiostate jsval read only.

nsISmsService
to create an instance, use: var smsservice = components.classes["@mozilla.org/sms/smsservice;1"] .createinstance(components.interfaces.nsismsservice); method overview [implicit_jscontext] nsidommozsmsmessage createsmsmessage(in long id, in domstring delivery, in domstring sender, in domstring receiver, in domstring body, in jsval timestamp, in bool read ); unsigned short getnumberofmessagesfortext(in domstring text); boolean hassupport(); void send(in domstring number, in domstring message, in long requestid, [optional] in unsigned long long processid); methods createsmsmessage() [implicit_jscontext] nsidommozsmsmessage createsmsmessage( in long id, in domstring delivery, in domst...
...ring sender, in domstring receiver, in domstring body, in jsval timestamp, in bool read ); parameters id a number representing the id of the message.

nsIVariant
jsval getasjsval(); native code only!
...(the reference count of the object is incremented.) native code only!getasjsval jsval getasjsval(); parameters none.

WebIDL bindings
likewise, a dictionary struct can be converted to a js::value in c++ by calling tojsvalue with the dictionary as the second argument.
... if init() or tojsvalue() returns false, they will generally set a pending exception on the jscontext; reporting those is the responsibility of the caller.

JS-Engine FAQ - Archive of obsolete content
check the jsval macros at the top of js/src/jsapi.h can an embedded spidermonkey js engine use domparser extension of mozilla?

Hacking Tips
5 in js::invoke(jscontext*, js::callargs const&, js::maybeconstruct) (cx=0x14f2640, args=..., construct=js::no_construct) at js/src/vm/interpreter.cpp:476 #3 0x000000000069bdcf in js::jit::docallfallback(jscontext*, js::jit::baselineframe*, js::jit::iccall_fallback*, uint32_t, js::value*, js::mutablehandlevalue) (cx=0x14f2640, frame=0x7fffffff6ad8, stub_=0x1798838, argc=1, vp=0x7fffffff6a88, res=jsval_void) at js/src/jit/baselineic.cpp:6113 #4 0x00007ffff7f41395 in <<jitframe_exit>> () #5 0x00007ffff7f42223 in <<jitframe_baselinestub>> () #6 0x00007ffff7f4423d in <<jitframe_baselinejs>> () #7 0x00007ffff7f4222e in <<jitframe_baselinestub>> () #8 0x00007ffff7f4326a in <<jitframe_baselinejs>> () #9 0x00007ffff7f38d5f in <<jitframe_entry>> () #10 0x00000000006a86de in enterbaseline(jscontex...

Invariants
(the jsval encoding depends on this.) the jsstackframe::down chain never forms a cycle.

Tracing JIT
it then imports the set of jsval values from the spidermonkey interpreter that the trace is known to read or write during its execution.

SpiderMonkey Internals
each property has an id, either a nonnegative integer or an atom (unique string), with the same tagged-pointer encoding as a jsval.

JSClass.call
the custom object that was called is jsval_to_object(js_argv_callee(argv)).

JSClass.flags
the slots initially contain unspecified valid jsval values.

JSMarkOp
use jsval_is_gcthing to check whether a value needs to be marked and jsval_to_gcthing to convert the jsval to a pointer.

JS_DefineOwnProperty
descriptor js::handlevalue this should be an jsval consisting of an object interpretable as property descriptor.

JS_DumpNamedRoots
it points to a variable, array element, or field of type jsval, jsobject *, jsstring *, or jsdouble *.

JS_GetPropertyDefault
syntax bool js_getpropertydefault(jscontext *cx, jsobject *obj, const char *name, jsval def, js::mutablehandle<js::value> vp); bool js_getpropertybyiddefault(jscontext *cx, jsobject *obj, jsid id, jsval def, js::mutablehandle<js::value> vp); name type description cx jscontext * a context.

JS_LooselyEqual
comparing jsvals directly in c++, as in v1 == v2, does not produce a meaningful result, since it is possible for two distinct jsstrings or jsdoubles to represent the same string or number.

JS_PopArguments
description js_poparguments frees the stack frame pointer previously allocated by js_pusharguments and unroots the jsvals which have been associated with it (those returned by js_pusharguments as well).

JS_SetPrivate
if your class's private data contains any jsvals or other references to javascript objects, implement the jsclass.mark callback to ensure they are not prematurely reclaimed by the garbage collector.

JS_THREADSAFE
jsbool socket_recv(jscontext *cx, unsigned int argc, jsval *vp) { ...

JS_ValueToFunction
instead, use jsval_is_object and js_objectisfunction() to check whether a value is already a function, or use js_convertvalue() to convert a value to jstype_function safely.

JS_ValueToObject
if v is jsval_null or jsval_void, the result is null.

Stored value
the javascript engine sets aside a field of type jsval for the stored value of most object properties, even properties that have getters.

jsid
a jsid is not implicitly convertible to or from a jsval; js_valuetoid or js_idtovalue must be used instead.

SpiderMonkey 1.8.8
deleted apis js_get_class (use js_getclass instead) js_constructobject and js_constructobjectwitharguments (preferably use js_new instead, or use this reimplementation as a short-term fix) js_newcompartmentandglobalobject (use js_newglobalobject instead.) jspd_argument jsval_is_object() (use !jsval_is_primitive(v) to detect objects and jsval_is_null(v) to detect null).

SpiderMonkey 17
deleted apis js_get_class (use js_getclass instead) js_constructobject and js_constructobjectwitharguments (preferably use js_new instead, or use this reimplementation as a short-term fix) js_newcompartmentandglobalobject (use js_newglobalobject instead.) jspd_argument jsval_is_object() (use !jsval_is_primitive(v) to detect objects and jsval_is_null(v) to detect null).

Secure Development Guidelines
o); foo++; printf(“foo: 0x%08x\r\n”, foo); } integer overflows/underflows example of an integer underflow int main() { unsigned int foo = 0; printf(“foo: 0x%08x\r\n”, foo); foo--; printf(“foo: 0x%08x\r\n”, foo); } integer overflows/underflows real-life example (bug 303213) jsbool js_str_escape(jscontext *cx, jsobject *obj, unsigned int argc, jsval *argv, jsval *rval){ ...

Index
559 nsidispatchsupport interfaces, xpcom, xpcom interface reference converts a com variant to a jsval.

inIDOMUtils
ted by: @mozilla.org/inspector/dom-utils;1 as a service: var inidomutils = components.classes["@mozilla.org/inspector/dom-utils;1"] .getservice(components.interfaces.inidomutils); method overview void addpseudoclasslock(in nsidomelement aelement, in domstring apseudoclass); void clearpseudoclasslocks(in nsidomelement aelement); [implicit_jscontext] jsval colornametorgb(in domstring acolorname); nsiarray getbindingurls(in nsidomelement aelement); nsidomnodelist getchildrenfornode(in nsidomnode anode, in boolean ashowinganonymouscontent); unsigned long long getcontentstate(in nsidomelement aelement); void getcsspropertynames([optional] in unsigned long aflags, [optional] out unsigned long acount, [retval, array,...

nsIDOMGlobalPropertyInitializer
method overview jsval init(in nsidomwindow window); methods init() jsval init( in nsidomwindow window ); parameters window the window to which the global property is being attached.

nsIFrameScriptLoader
methods void loadframescript(in astring aurl, in boolean aallowdelayedload, [optional] in boolean aruninglobalscope) void removedelayedframescript(in astring aurl); jsval getdelayedframescripts(); loadframescript() load a script in the remote frame.

nsIMessageBroadcaster
methods void broadcastasyncmessage([optional] in astring messagename, [optional] in jsval obj, [optional] in jsval objects); nsimessagelistenermanager getchildat(in unsigned long aindex); broadcastasyncmessage() like sendasyncmessage(), but also broadcasts this message to all "child" message managers of this message manager.

nsIMessageSender
methods void sendasyncmessage([optional] in astring messagename, [optional] in jsval obj, [optional] in jsval objects, [optional] in nsiprincipal principal); sendasyncmessage() send messagename and obj to the "other side" of this message manager.

nsIProcessScriptLoader
methods void loadprocessscript(in astring aurl, in boolean aallowdelayedload) void removedelayedprocessscript(in astring aurl); jsval getdelayedprocessscripts(); loadprocessscript() load a script in the child process.

nsISessionStartup
state jsval the session state, as a javascript object.

nsIStructuredCloneContainer
void initfromvariant( in nsivariant adata ); parameters adata a nsivariant, must be backed by a jsval.

nsISyncMessageSender
methods jsval sendsyncmessage([optional] in astring messagename, [optional] in jsval obj, [optional] in jsval objects, [optional] in nsiprincipal principal); jsval sendrpcmessage([optional] in astring messagename, [optional] in jsval obj, [optional] in jsval objects, ...

WebAssembly.validate() - JavaScript
desktopmobileserverchromeedgefirefoxinternet exploreroperasafariandroid webviewchrome for androidfirefox for androidopera for androidsafari on iossamsung internetnode.jsvalidatechrome full support 57edge full support 16firefox full support 52notes full support 52notes notes disabled in the firefox 52 extended support release (esr).ie no support ...