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/*
* The order of checks and coercions for a property access are defined
* by the property accessor evaluation rules in E5 Section 11.2.1,
* GetValue() in E5 Section 8.7.1, and finally [[Get]].
*
* In short:
*
* - CheckObjectCoercible for base reference. TypeError for null and
* undefined. (E5 Section 11.2.1 step 5)
*
* - ToString for property name. This may have side effects and thus
* order matters. (E5 Section 11.2.1 step 6).
*
* - ToObject for base reference. (E5 Section 8.7.1, special [[Get]],
* step 1)
*
*/
var t = {}
t.toString = function() { print("toString() called"); return "foo"; };
/*===
TypeError
===*/
// CheckObjectCoercible fails, toString() doesn't get called
try {
null[t] = 'bar';
} catch (e) {
print(e.name);
}
/*===
toString() called
bar
===*/
// CheckObjectCoercible succeeds, toString() gets called
try {
var o = {};
o[t] = 'bar';
print(o.foo);
} catch (e) {
print(e.name);
}