What's the meaning of strict reference flag in ECMA 5 262
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I was reading ECMA 5 262, and feel confused on the term "strict reference" in http://es5.github.com/#IsStrictReference:

> A Reference is a resolved name binding. A Reference consists of three components, the base value, the referenced name and the Boolean valued strict reference flag. The base value is either undefined, an Object, a Boolean, a String, a Number, or an environment record (10.2.1). A base value of undefined indicates that the reference could not be resolved to a binding. The referenced name is a String.

There's not much description on it. The only related operation on Reference is 

> IsStrictReference(V). Returns the strict reference component of the reference V.

but no operation to set, neither description how we can decide the value. 

I guess it must be related to the strict mode, but how can i tell what's the value for a specific Reference?

