NAME

Lingua::EN::PluralToSingular - change an English plural to a singular

SYNOPSIS

use Lingua::EN::PluralToSingular qw/to_singular is_plural/;
my @words = qw/knives sheep dog dogs cannabis/;
for my $word (@words) {
    if (is_plural ($word)) {
        my $sing = to_singular ($word);
        print "The singular of '$word' is '$sing'.\n";
    }
    else {
        print "'", ucfirst ($word), "' is not plural.\n";
    }
}

produces output

The singular of 'knives' is 'knife'.
The singular of 'sheep' is 'sheep'.
'Dog' is not plural.
The singular of 'dogs' is 'dog'.
'Cannabis' is not plural.

(This example is included as synopsis.pl in the distribution.)

VERSION

This documents Lingua::EN::PluralToSingular version 0.21 corresponding to git commit 2d53254eeaec8d2006655f63f61b4f6868e81153 released on Thu Jun 21 17:48:56 2018 +0900.

DESCRIPTION

This converts words denoting a plural in the English language into words denoting a singular noun.

FUNCTIONS

to_singular

my $singular = to_singular ($word);

Convert $word into its singular form. For example,

to_singular ('cats')

returns 'cat'. If the word is unknown or does not seem to be plural, to_singular returns the word itself, so

to_singular ('battlehorn');

returns 'battlehorn'.

is_plural

if (is_plural ($word)) {
    print "There are too many $word here.\n";
}
else {
    print "There is a $word here.\n";
}

Returns 1 if the word is a valid plural, 0 if not. It also returns 1 for ambiguous words like "sheep".

LIMITATIONS AND CAVEATS

Assumes the input is a noun

"to_singular" assumes its input is a noun. For example, "lives" may be the plural of "life", or the verb "live", as in "he lives". The routine assumes a noun and converts to "life".

Distinguishes lower and upper case

It does not deal with capitalized words. If the input word may be capitalized, or if its initial letter may be capitalized, the user must preprocess it to put it into the normal case. So, for example,

to_singular ('FLIES');

returns 'FLIES' and

to_singular ('Wolves');

returns 'Wolve'. Similarly,

to_singular ('Charles');

returns 'Charles', but

to_singular ('charles');

returns 'charle', since the exception only applies if the word is capitalized.

Does not handle pronouns

The module does not attempt to handle pronoun forms like "ourselves" or "themselves". These words are left unaltered.

False plurals also accepted

For the sake of user convenience, false plurals like "octopi" are also accepted by the module. (The plural of "octopus" is "octopuses".)

Not all exceptional plurals are included

There are many exceptions which have not been included, notably words with Latin or Greek plurals.

STANDALONE SCRIPT

The script scripts/singular provides a quick way to get singular versions of nouns:

singular cats dogs geese
# Prints "cat dog goose".

SEE ALSO

Lingua::EN::Inflect

Lingua::EN::Inflect by Damian Conway converts English singular nouns to plurals, but not vice-versa.

Lingua::EN::Inflect::Number

Lingua::EN::Inflect::Number is supposed to do the same thing as this module. However, as of the time of writing (version 1.12) it's actually based on the third-person verb handling of Lingua::EN::Inflect, in other words it takes a verb in the "he says" form and converts it into "say". Thus you get bugs like https://rt.cpan.org/Public/Bug/Display.html?id=64564 where the reporter demonstrates that 'to_S incorrectly renders the singular of "statuses" as "statuse."'

ACKNOWLEDGEMENTS

Thanks to Xan Charbonnet and H2CHANG for various additions and fixes. Lisa Hare contributed support for plurals ending in i as part of the 2016 Pull Request Challenge.

AUTHOR

Ben Bullock, <bkb@cpan.org>

COPYRIGHT & LICENCE

This package and associated files are copyright (C) 2011-2018 Ben Bullock.

You can use, copy, modify and redistribute this package and associated files under the Perl Artistic Licence or the GNU General Public Licence.