5.14.0

CHANGELOG.md

@@ -1,3 +1,11 @@
+## [5.14.0](https://github.com/shivam091/unit_measurements/compare/v5.13.0...v5.14.0) - 2023-11-29
+
+### What's new
+
+- Added `.define_numeric_methods` support to define numeric extension methods for units.
+
+----------
+
 ## [5.13.0](https://github.com/shivam091/unit_measurements/compare/v5.12.0...v5.13.0) - 2023-11-27
 
 ### What's new

Gemfile.lock

@@ -1,7 +1,7 @@
 PATH
   remote: .
   specs:
-    unit_measurements (5.13.0)
+    unit_measurements (5.14.0)
       activesupport (~> 7.0)
 
 GEM

README.md

@@ -482,6 +482,31 @@ Length = UnitMeasurements::Length
 Volume = UnitMeasurements::Volume
 ```
 
+## Extras
+
+### Numeric extension methods
+
+The `.define_numeric_methods` method allows you to instantiate measurements in a
+manner similar to how `ActiveSupport::Duration` objects are created in Rails,
+providing a familiar syntax and functionality.
+
+To define numeric extension methods for specific units within a unit group, use
+the following syntax:
+
+```ruby
+UnitMeasurements::Length.define_numeric_methods("metre", "foot", "inch")
+```
+
+This will enable the usage of these units as methods to instantiate and use measurements:
+
+```ruby
+1.m                 #=> Instantiate a measurement representing 1 metre.
+5.feet              #=> Instantiate a measurement representing 5 feet.
+10.inches           #=> Instantiate a measurement representing 10 inches.
+1.foot == 12.inches #=> equality comparison between two measurements.
+1.ft + 12.in        #=> adds quantity of two measurements.
+```
+
 ## Contributing
 
 1. Fork it

lib/unit_measurements/base.rb

@@ -151,6 +151,8 @@ def configure
 end
 
 # The following requires load various components of the unit measurements library.
+require "unit_measurements/extras/numeric_methods"
+
 require "unit_measurements/configuration"
 require "unit_measurements/cache"
 require "unit_measurements/unit_group_builder"

lib/unit_measurements/extras/numeric_methods.rb

@@ -0,0 +1,81 @@
+# -*- encoding: utf-8 -*-
+# -*- frozen_string_literal: true -*-
+# -*- warn_indent: true -*-
+
+module UnitMeasurements
+  # This module provides methods to define +Numeric+ extension methods for a list
+  # of units within a unit group. If units are empty, it defaults to defining
+  # methods for all units in the unit group.
+  #
+  # This module is included in the +Measurement+ class to allow defining numeric
+  # extension methods for specified units.
+  #
+  # @see Measurement
+  #
+  # @author {Harshal V. Ladhe}[https://shivam091.github.io/]
+  # @since 5.14.0
+  module NumericMethods
+    # @scope class
+    # Defines +Numeric+ extension methods for specified units within the unit
+    # group. If units are empty, it defaults to defining methods for all units
+    # within the unit group.
+    #
+    # @param [Array<String|Symbol>] units
+    #   An array of units' names for which numeric methods need to be defined.
+    #   If empty, methods will be defined for all units in the unit group.
+    #
+    # @return [Array<Unit>] An array of units for which methods are defined.
+    #
+    # @example Define numeric methods for metres, centimetres, and millimetres:
+    #   UnitMeasurements::Length.define_numeric_methods("metres", :cm, :mm)
+    #
+    # @example Define numeric methods for all units in the unit group:
+    #   UnitMeasurements::Length.define_numeric_methods
+    #
+    # @see #define_numeric_method_for
+    #
+    # @author {Harshal V. Ladhe}[https://shivam091.github.io/]
+    # @since 5.14.0
+    def define_numeric_methods(*units)
+      unit_group = self
+      units = units.empty? ? unit_group.units : units
+
+      units.inject([]) do |units, unit|
+        units << define_numeric_method_for(unit, unit_group)
+      end
+    end
+
+    private
+
+    # @private
+    # @scope class
+    # This method defines a numeric method for a specific unit within a unit group.
+    # The method is defined dynamically using +define_method+ and associates the
+    # unit with the numeric value.
+    #
+    # @param [String|Symbol|Unit] unit
+    #   The unit for which the numeric method is defined.
+    # @param [UnitGroup] unit_group The unit group to which the unit belongs.
+    #
+    # @return [Unit] The unit instance for which the method was defined.
+    #
+    # @see #define_numeric_methods
+    #
+    # @author {Harshal V. Ladhe}[https://shivam091.github.io/]
+    # @since 5.14.0
+    def define_numeric_method_for(unit, unit_group)
+      unit = unit.is_a?(Unit) ? unit : unit_group.unit_for!(unit)
+
+      unit.names.each do |method_name|
+        # Check if the name contains alphabetic characters
+        next unless method_name =~ /^[a-zA-Z]+$/
+
+        Numeric.define_method(method_name) do
+          unit_group.new(self, unit)
+        end
+      end
+
+      unit
+    end
+  end
+end

lib/unit_measurements/measurement.rb

@@ -23,6 +23,7 @@ module UnitMeasurements
   # @see Conversion
   # @see Formatter
   # @see Math
+  # @see NumericMethods
   # @author {Harshal V. Ladhe}[https://shivam091.github.io/]
   # @since 1.0.0
   class Measurement
@@ -32,6 +33,8 @@ class Measurement
     include Formatter
     include Math
 
+    extend NumericMethods
+
     # Regular expression to match conversion strings.
     #
     # @author {Harshal V. Ladhe}[https://shivam091.github.io/]

lib/unit_measurements/version.rb

@@ -4,5 +4,5 @@
 
 module UnitMeasurements
   # Current stable version.
-  VERSION = "5.13.0"
+  VERSION = "5.14.0"
 end

spec/unit_measurements/extras/numeric_methods_spec.rb

@@ -0,0 +1,33 @@
+# -*- encoding: utf-8 -*-
+# -*- frozen_string_literal: true -*-
+# -*- warn_indent: true -*-
+
+# spec/unit_measurements/extras/numeric_methods_spec.rb
+
+RSpec.describe UnitMeasurements::NumericMethods do
+  let(:unit_group) { UnitMeasurements::Length }
+  let(:m) { unit_group.unit_for!(:m) }
+  let(:cm) { unit_group.unit_for!(:cm) }
+
+  context "when units are specified" do
+    it "defines extension methods for specified units" do
+      unit_group.define_numeric_methods("m", "cm")
+
+      expect(Numeric.method_defined?("m")).to be_truthy
+      expect(Numeric.method_defined?("cm")).to be_truthy
+
+      expect(1.cm).to be_instance_of(unit_group)
+    end
+  end
+
+  context "when units are specified" do
+    it "defines extension methods for all units within the unit group" do
+      unit_group.define_numeric_methods
+
+      expect(Numeric.method_defined?("ft")).to be_truthy
+      expect(Numeric.method_defined?("in")).to be_truthy
+
+      expect(1.ft).to be_instance_of(unit_group)
+    end
+  end
+end