Script.apex

Script.apex help you run JavaScript code in Apex. Basically, it compiles JavaScript code into semantic nodes, which are then evaluated in native Apex. The JavaScript expression parser in Script.apex is porting from jsep.

Features

• Parse JavaScript code into semantic nodes
• Evaluate nodes in Apex
• Parsed nodes are cached to improve performance

Usage

Here is how we evaluate arithmatic expressions.

Objectresult = ScriptEngine.getInstance().eval('1 + 2 * (3 - 1)');

Or we can evaluate expressions consuming variables like this:

Map<String, Object> context = newMap<String, Object>{
'a' => 1,
'b' => 2
};
Objectresult = ScriptEngine.getInstance().eval('a + b', context);

Or we can parse the nodes first, and the evaluate them:

Jsep.Nodenode = newJsep('1 + 2').parse();
Objectresult = ScriptEngine.getInstance().eval(node);

Supported Operations

Supported Unary Operator

Name	Description
-	Negate number
!	Negate boolean
++	Only prefix supported
--	Only prefix supported

Supported Logical Operator

Name	Description
&&	Logical and
||	Logical or

Supported Binary Operator

Name	Description
==	Apex ==
!=	Apex !=
===	Apex ==
!==	Apex !=
<	Apex <
>	Apex >
<=	Apex <=
>=	Apex >=
+	Apex +
-	Apex -
*	Apex *
/	Apex /
%	Apex Math.mod

Supported Structure

Name	Description
Conditional Expression(? :)	Yes
Array Literal	Yes
Object Literal	Yes

For example,

ScriptEngine.getInstance.eval('["a", "b"]'); // Array literalScriptEngine.getInstance.eval('{ "name": "test", age: 18 }'); // Object literal

Todos

Assignment Expression Evaluation

Assignment expressions can be parsed, but cannot be evaluated yet.

Function Invocation

Functions(methods) can be parsed now, but invocation is not implemented yet.