RosettaCodeData/Task/String-comparison/00DESCRIPTION

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{{basic data operation}} [[Category:Basic language learning]] [[Category:Simple]]
The task is to demonstrate how to compare two strings from within the language and how to achieve a lexical comparison.
The task should demonstrate:
* Comparing two strings for exact equality
* Comparing two strings for inequality (i.e., the inverse of exact equality)
* Comparing two strings to see if one is lexically ordered before than the other
* Comparing two strings to see if one is lexically ordered after than the other
* How to achieve both case sensitive comparisons and case insensitive comparisons within the language
* How the language handles comparison of numeric strings if these are not treated lexically
* Demonstrate any other kinds of string comparisons that the language provides, particularly as it relates to your type system.   For example, you might demonstrate the difference between generic/polymorphic comparison and coercive/allomorphic comparison if your language supports such a distinction.
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Here "generic/polymorphic" comparison means that the function or operator you're using doesn't always do string comparison, but bends the actual semantics of the comparison depending on the types one or both arguments; with such an operator, you achieve string comparison only if the arguments are sufficiently string-like in type or appearance.
In contrast, a "coercive/allomorphic" comparison function or operator has fixed string-comparison semantics regardless of the argument type; &nbsp; instead of the operator bending, it's the arguments that are forced to bend instead and behave like strings if they can, &nbsp; and the operator simply fails if the arguments cannot be viewed somehow as strings. &nbsp; A language may have one or both of these kinds of operators; &nbsp; see the Perl 6 entry for an example of a language with both kinds of operators.
;Related tasks:
* &nbsp; [[Integer comparison]]
* &nbsp; [[String matching]]
* &nbsp; [[Compare a list of strings]]
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