Just add this review to link to Ben Bullock's Lingua::EN::PluralToSingular if you need to go the other way (converting English noun from plural to singular).
BTW, I don't like the interface either, and wonder why the Env module needs to be involved.
Lingua::EN::Inflect is a module to adjust single English words with indefinite articles (a/an) or plural and singular. There are various subroutines to turn words into their plurals or add articles. These seem to work well and handle all the usual exceptions like "child/children", "goose/geese", "a university/an upstart" as required, so this module may well be enough for people who want to output correctly formatted text as output from a computer program.
However, I got stuck when I wanted to use this to analyze input. The module does not have an interface to detect if a noun is plural or singular. This seemed very strange since the module's plural comparison functions must have that ability in order to do their work. Internally there is a routine which does this job, called _PL_check_plurals_N, but unfortunately it is not available in the public interface.
The naming and behaviour of the routines is a bit strange. For example "PL" for plural, but the same thing is also used to convert a verb from the third person singular form. For example PL("cat") gives you "cats" as output, but PL("cats") gives you "cat" as output. I don't see when that would be useful, it's a bad idea, and that is not related to plural: "I eat" and "we eat" are singular and plural forms of the same sentence, but the verb doesn't change.
As I said at the top this is probably good enough for the case when you are generating sentences via the computer and want to get your "a/an" and singular and plurals right. So basically it fulfils its purpose. However, that is about all it does, the name "Inflect" is a little pretentious considering this module's functionality.
(Contact me at firstname.lastname@example.org if you have a comment about this review.)
I hate the interface -- but I'm not sure what would be better. It hardly matters: the module is so darn useful that you'll stop caring about the interface really quickly. I don't use it often, but when I do, it keeps me from looking like an idiots.
The most general solution if you want to stop your application from saying ugly things like "found 1 results". Handles the crazy inconsistencies of English pretty well.
The documentation looks long and intimidating at first sight, but that's because it is full of special cases to handle many of the nuances of natural language.
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