Method _compile

src/expression/node/OperatorNode.js:292–335

* Compile a node into a JavaScript function. * This basically pre-calculates as much as possible and only leaves open * calculations which depend on a dynamic scope with variables. * @param {Object} math Math.js namespace with functions and constants. * @param {Object} argNam

(math, argNames)

     *                        evalNode(scope: Object, args: Object, context: *)
     */
    _compile (math, argNames) {
      // validate fn
      if (typeof this.fn !== 'string' || !isSafeMethod(math, this.fn)) {
        if (!math[this.fn]) {
          throw new Error(
            'Function ' + this.fn + ' missing in provided namespace "math"')
        } else {
          throw new Error('No access to function "' + this.fn + '"')
        }
      }

      const fn = getSafeProperty(math, this.fn)
      const evalArgs = map(this.args, function (arg) {
        return arg._compile(math, argNames)
      })

      if (typeof fn === 'function' && fn.rawArgs === true) {
        // pass unevaluated parameters (nodes) to the function
        // "raw" evaluation
        const rawArgs = this.args
        return function evalOperatorNode (scope, args, context) {
          return fn(rawArgs, math, createSubScope(scope, args))
        }
      } else if (evalArgs.length === 1) {
        const evalArg0 = evalArgs[0]
        return function evalOperatorNode (scope, args, context) {
          return fn(evalArg0(scope, args, context))
        }
      } else if (evalArgs.length === 2) {
        const evalArg0 = evalArgs[0]
        const evalArg1 = evalArgs[1]
        return function evalOperatorNode (scope, args, context) {
          return fn(
            evalArg0(scope, args, context),
            evalArg1(scope, args, context))
        }
      } else {
        return function evalOperatorNode (scope, args, context) {
          return fn.apply(null, map(evalArgs, function (evalArg) {
            return evalArg(scope, args, context)
          }))
        }
      }
    }

    /**
     * Execute a callback for each of the child nodes of this node