This article covers features introduced in SpiderMonkey 17
Compile and execute a script.
Syntax
// Added in SpiderMonkey 45 bool JS::Evaluate(JSContext *cx, const JS::ReadOnlyCompileOptions &options, JS::SourceBufferHolder &srcBuf, JS::MutableHandleValue rval); bool JS::Evaluate(JSContext *cx, const JS::ReadOnlyCompileOptions &options, const char16_t *chars, size_t length, JS::MutableHandleValue rval); bool JS::Evaluate(JSContext *cx, const JS::ReadOnlyCompileOptions &options, const char *bytes, size_t length, JS::MutableHandleValue rval); bool JS::Evaluate(JSContext *cx, const JS::ReadOnlyCompileOptions &options, const char *filename, JS::MutableHandleValue rval); bool JS::Evaluate(JSContext *cx, JS::AutoObjectVector &scopeChain, const ReadOnlyCompileOptions &options, const char16_t *chars, size_t length, JS::MutableHandleValue rval); // Added in SpiderMonkey 17 bool JS::Evaluate(JSContext *cx, JS::AutoObjectVector &scopeChain, const JS::ReadOnlyCompileOptions &options, JS::SourceBufferHolder &srcBuf, JS::MutableHandleValue rval); // Obsolete since JSAPI 39 bool JS::Evaluate(JSContext *cx, JS::HandleObject obj, const JS::ReadOnlyCompileOptions &options, JS::SourceBufferHolder &srcBuf, JS::MutableHandleValue rval); bool JS::Evaluate(JSContext *cx, JS::HandleObject obj, const JS::ReadOnlyCompileOptions &options, const char16_t *chars, size_t length, JS::MutableHandleValue rval); bool JS::Evaluate(JSContext *cx, JS::HandleObject obj, const JS::ReadOnlyCompileOptions &options, const char *bytes, size_t length, JS::MutableHandleValue rval); bool JS::Evaluate(JSContext *cx, JS::HandleObject obj, const JS::ReadOnlyCompileOptions &options, const char *filename, JS::MutableHandleValue rval);
Name | Type | Description |
---|---|---|
cx |
JSContext * |
The context in which to run the script. Requires request. In a JS_THREADSAFE build, the caller must be in a request on this JSContext . |
obj |
JS::HandleObject |
The scope in which to execute the script. This parameter is documented in detail at . Obsolete since JSAPI 39 |
scopeChain |
JS::AutoObjectVector & |
The scope in which to execute the script. This parameter is documented in detail at . |
options |
JS::ReadOnlyCompileOptions & |
Compile options. |
srcBuf |
JS::SourceBufferHolder & |
Source buffer containing the script to compile and execute. |
chars |
const char16_t * |
String containing the script to compile and execute. |
bytes |
const char * |
String containing the script to compile and execute. |
length |
size_t |
The length of chars or bytes , in characters. |
filename |
const char * |
Name of file or URL containing the script. Used to report filename or URL in error messages. |
rval |
JS::MutableHandleValue |
Out parameter. On success, if rval is not NULL , *rval receives the result value. |
Description
JS::Evaluate
compiles and executes a script in the specified scope, obj
or scopeChain
.
srcBuf
, chars
and bytes
are the string containing the text of the script. length
indicates the size of the text version of the script in characters.
filename
is the name of the file (or URL) containing the script. This information is used in messages if an error occurs during compilation.
rval
is an optional out parameter. If it is non-null, then on success, the result value is stored in *rval
. This value is determined the same way as for the standard eval
function. In the common case where the script is just an expression, the result value is simply the value of that expression. More generally, the result value is the value of the last-executed expression statement in the script that isn't in a function.
If a script compiles and executes successfully, JS::Evaluate
stores the result in *rval
, if non-null, and returns true
. Otherwise it returns false
and the value left in *rval
is undefined.
See Also
- MXR ID Search for
JS::Evaluate
JS::Compile
JS_ExecuteScript
- bug 771705
- bug 1097987 -- remove
obj
parameter