InscrutableCode: Lexicographic Ordering in Javascript

InscrutableCode is a place where I document particularly nasty broken things that I encounter as a software developer. Partly to inform, mostly as therapy.

In lexicographic ordering (from Wikipedia):

Given two different words of the same length, say a = a₁a₂...a_k and b = b₁b₂...b_k, the order of the two words depends on the alphabetic order of the symbols in the first place i where the two words differ (counting from the beginning of the words): a < b if and only if a_i < b_i in the underlying order of the alphabet A.

This means that  str1 > str2 implies that str1 + prefix1 > str2 + prefix2, for any prefix1 and prefix2.

Javascript violates this basic property of string comparison.

'é'.localeCompare('e')    //  1 which means é > e 
'éa'.localeCompare('eb')  // -1 which means éa < eb