2.1.10 [ECMA-262/5] Section 18.104.22.168, String.prototype.localeCompare (that)
The actual return values are implementation-defined to permit implementers to encode additional information in the value, but the function is required to define a total ordering on all Strings and to return 0 when comparing Strings that are considered canonically equivalent by the Unicode standard.
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The returned value is determined as follows:
Call the Microsoft Windows CompareString system function, passing
that, and the current locale information as arguments.
Pass the value
0as the dwCmpFlags argument.
Return result (