NAME¶
JE::Code - ECMAScript parser and code executor for JE
SYNOPSIS¶
use JE;
$j = new JE;
$code = $j->compile('1+1'); # returns a JE::Code object
$code->execute;
METHODS¶
- $code->execute($this, $scope, $code_type);
- The "execute" method of a parse tree executes it. All the
arguments are optional.
The first argument will be the 'this' value of the execution context. The
global object will be used if it is omitted or undef.
The second argument is the scope chain. A scope chain containing just the
global object will be used if it is omitted or undef.
The third arg indicates the type of code. 0 or undef indicates
global code. 1 means eval code (code called by JavaScript's
"eval" function, which has nothing to do with JE's
"eval" method, which runs global code). Variables created with
"var" and function declarations inside eval code can be deleted,
whereas such variables in global or function code cannot. A value of
2 means function code, which requires an explicit
"return" statement for a value to be returned.
If an error occurs, "undef" will be returned and $@ will contain
the error message. If no error occurs, $@ will be a null string.
- $code->set_global( $thing )
- You can transfer a JE::Code object to another JavaScript environment by
setting the global object this way. You can also set it to
"undef", if, for instance, you want to serialise the compiled
code without serialising the entire JS environment. If you do that, you'll
need to set the global object again before you can use the code
object.
FUNCTIONS¶
- JE::Code::add_line_number($message, $code_object, $position)
- WARNING: The parameter list is still subject to change.
This routine append a string such as 'at file, line 76.' to the error
message passed to it, unless it ends with a line break already.
$code_object is a code object as returned by JE's or JE::Parser's
"parse" method. If it is omitted, the current value of
$JE::Code::code will be used (this is set while JS code is running). If
$JE::Code::code turns out to be undefined, then $message will be returned
unchanged ( this is subject to change; later I might make it use
Carp to add a Perl file and line number).
$position is the position within the source code, which will be used to
determine the line number. If this is omitted, $JE::Code::pos will be
used.
EXPORTS¶
"add_line_number" can optionally be exported.
SEE ALSO¶
- JE