Include 'an's along with 'a's as an article

[dhruvkb]

Problem

In many places the indefinite article 'a' is manipulated, either by stripping it away or treating it as 1. The article 'an' should be processed in the same way.

In all these regexes a should be replaced with an? to cover both articles.

Occurrences

numerizer/lib/providers/english_provider.rb

Line 110 in 31c1b1f

string.gsub!(/\ba$/, '') && string.rstrip! # doesn't make sense for an 'a' at the end to be a 1

numerizer/lib/providers/english_provider.rb

Line 124 in 31c1b1f

string.gsub!(/(^|\W)\ba\b(?=$|\W)(?! (?:#{ALL_ORDINALS_REGEX}))/i, '\1<num>' + 1.to_s)

numerizer/lib/providers/english_provider.rb

Line 126 in 31c1b1f

string.gsub!(/(^|\W)\ba\b(?=$|\W)/i, '\1<num>' + 1.to_s)

Resolution

I could make a PR if there's consensus that this needs to be fixed.

[jduff]

Can you give a few examples of the test cases you would make pass with this change? I can't think of the cases where you would have an instead of a and want it treated the same way. I also haven't spent much time with this codebase in awhile now so may just be missing the context for this.

[dhruvkb]

Sure, I can give some examples.

Words	Numerized
an eighth	1/8
an eleventh	1/11

You wouldn't use "a" as the article on words starting with vowels.

[jduff]

I forgot about fractions lol.

If you want to submit a PR for this I'll take a look, thanks!