eval-expression
Evaluate an expression and get what you expect.
Be warned: Take all precausions which apply to using eval. eval-expression is no safer, no more performant and no easier to debug.
But it is more predictable. And, just as eval, it sometimes is useful for rapid prototyping.
Installation
> npm install eval-expressionUsage
var evalExpression = require("eval-expression");
// `eval` fails with function expressions β `evalExpression` handles them.
var sayHello = evalExpression('function () {console.log("Hello!");}');
sayHello(); // Logs: Hello!
// `eval` fails with object literals β `evalExpression` does what you expect.
var fruit = evalExpression('{sort: "pear"}');
fruit; // Outputs: {sort: "pear"}
// You can access variables in the current scope.
console.log(evalExpression("fruit")); // Outputs: {sort: "pear"}
// `evalExpression` is only intended to evaluate expressions, not other
// statements.
var tasty;
// So don't do this:
evalExpression('if (fruit.sort == "pear") {tasty = true}'); // Throws
// Do this instead:
tasty = evalExpression('fruit.sort == "pear" ? true : false'); // Outputs: true
// β¦or even:
tasty = evalExpression('fruit.sort == "pear"'); // Outputs: trueAPI
evalExpression(expression)
expression
Type:
String
Required
A single expression. It will be evaluated in an enclosed scope.
Why use it
eval doesn't always work as you'd expect. See these cases:
License
MIT Β© Tomek Wiszniewski.
