Calyx cannot handle string methods that accept parameters

[tra38]

The good news is that I am right now using Calyx in a real-world project. The bad news is that doing so means you quickly encounter edge cases...

---

Sometimes, your program has to generate sentences without knowing in advance if they'd be plural or not.

class CatWatch < Calyx::Grammar
   start "Today, I saw {number} cats on the way to work."
end

reporter = CatWatch.new
reporter.generate(number: 1)
#=>"Today, I saw 1 cats on my way to work."

I thought about doing some monkey-patching to handle this sort of pluralization, with plans to eventually refactor to a "best practice" solution using modifiers...

class String
   def pluralize(possible_word)
      if self.to_i == 1
         "#{self} #{possible_word}"
      else
         "#{self} #{possible_word}s"
      end
   end
end

"1".pluralize("cat")
#=>"1 cat"

"2".pluralize("cat")
#=>"2 cats"

However, this monkey-patched solution doesn't work in Calyx.

class CatWatch < Calyx::Grammar
   start "Today, I saw {number.pluralize('cat')} on the way to work."
end

reporter = CatWatch.new
reporter.generate(number: 1)
=>"Today, I saw {number.pluralize('cat')} on the way to work."

Refactoring to "best practice" doesn't work either.

module Pluralize
   def pluralize(possible_word)
      if self.to_i == 1
         "#{self} #{possible_word}"
      else
         "#{self} #{possible_word}s"
      end
   end
end

class CatWatch < Calyx::Grammar
   modifier Pluralize
   start "Today, I saw {number.pluralize('cat')} on the way to work."
end

reporter = CatWatch.new
reporter.generate(number: 1)
#=>Today, I saw {number.pluralize('cat')} on the way to work.

Even more oddly, if I do a slight change to the start method...it is no longer gets interpreted as part of the string...even though I still get incorrect output.

class CatWatch < Calyx::Grammar
   modifier Pluralize
   start "{number.pluralize('cat')}"
end

reporter = CatWatch.new
reporter.generate(number: 1)
#=>"1"

Now, since I'm on a tough deadline, I wind up doing this solution instead to handle pluralization.

class String
   def pluralize_cats
      if self.to_i == 1
         "#{self} cat"
      else
         "#{self} cats"
      end
   end
end

class CatWatch < Calyx::Grammar
   start "Today, I saw {number.pluralize_cats} on the way to work."
end

reporter = CatWatch.new
reporter.generate(number: 1)
#=>"Today, I saw 1 cat on the way to work."

...which "works", but is pretty hacky. There has to be a better solution (one that hopefully doesn't involve using meta programming to generate a bunch of unique methods for handling pluralization). It'll do for now though.

I decided to follow best practice by moving my pluralize_cats method over to a module, but I then encountered a different issue with modifiers (which I reported in #21).

[maetl]

The syntax limitation is by design, but I appreciate the feedback on this.

I’ll provide some recommendations once #21 is fixed.

[tra38]

In case anyone was curious, this was my final solution to this problem. If I get time, I'm going to look at Inflecto to see whether I can incorporate that library into this solution in case I ever need to deal with pluralization again.

module Macros

  def generate_pluralization_method(singular:, plural:)
    method_suffix = plural.gsub(" ","_")
    define_method :"pluralize_#{method_suffix}" do |argument|
      if (argument.to_f == 1)
        "#{argument} #{singular}"
      else
        "#{argument} #{plural}"
      end
    end
  end

end

module CatWatchHelpers
   extend Macros
   generate_pluralization_method(singular: "cat", plural: "cats")
end

class CatWatch < Calyx::Grammar
   modifier CatWatchHelpers
   start "Today, I saw {number.pluralize_cats} on the way to work."
end

reporter = CatWatch.new
reporter.generate(number: 1)
#=>Today, I saw 1 cat on the way to work.