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node_modules/core-js/internals/to-primitive.js

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+'use strict';
+var call = require('../internals/function-call');
+var isObject = require('../internals/is-object');
+var isSymbol = require('../internals/is-symbol');
+var getMethod = require('../internals/get-method');
+var ordinaryToPrimitive = require('../internals/ordinary-to-primitive');
+var wellKnownSymbol = require('../internals/well-known-symbol');
+
+var $TypeError = TypeError;
+var TO_PRIMITIVE = wellKnownSymbol('toPrimitive');
+
+// `ToPrimitive` abstract operation
+// https://tc39.es/ecma262/#sec-toprimitive
+module.exports = function (input, pref) {
+  if (!isObject(input) || isSymbol(input)) return input;
+  var exoticToPrim = getMethod(input, TO_PRIMITIVE);
+  var result;
+  if (exoticToPrim) {
+    if (pref === undefined) pref = 'default';
+    result = call(exoticToPrim, input, pref);
+    if (!isObject(result) || isSymbol(result)) return result;
+    throw $TypeError("Can't convert object to primitive value");
+  }
+  if (pref === undefined) pref = 'number';
+  return ordinaryToPrimitive(input, pref);
+};