added keyword arguments example

6 files changed, 101 insertions, 1 deletions

diff --git a/build_config.rb b/build_config.rb
index a7c77ff..773f579 100644
--- a/build_config.rb
+++ b/build_config.rb
@@ -5,6 +5,7 @@ MRuby::Build.new do |conf|
   # Use mrbgems
   conf.gem './mrb_gems/basic_example'
   conf.gem './mrb_gems/arguments_and_return_example'
+  conf.gem './mrb_gems/keyword_arguments_example'
   # conf.gem 'examples/mrbgems/ruby_extension_example'
   # conf.gem 'examples/mrbgems/c_extension_example' do |g|
   #   g.cc.flags << '-g' # append cflags in this gem
diff --git a/mrb_gems/keyword_arguments_example/LICENSE b/mrb_gems/keyword_arguments_example/LICENSE
new file mode 100644
index 0000000..a632bdf
--- /dev/null
+++ b/mrb_gems/keyword_arguments_example/LICENSE
@@ -0,0 +1,22 @@
+The MIT License (MIT)
+
+Copyright (c) 2023 Tradam
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+
diff --git a/mrb_gems/keyword_arguments_example/README.md b/mrb_gems/keyword_arguments_example/README.md
new file mode 100644
index 0000000..71eed2d
--- /dev/null
+++ b/mrb_gems/keyword_arguments_example/README.md
@@ -0,0 +1,2 @@
+# KeywordArgumentsExample
+An mruby gem created by Tradam using mruby_gem_scaffolding.
diff --git a/mrb_gems/keyword_arguments_example/mrbgem.rake b/mrb_gems/keyword_arguments_example/mrbgem.rake
new file mode 100644
index 0000000..6a1fc1e
--- /dev/null
+++ b/mrb_gems/keyword_arguments_example/mrbgem.rake
@@ -0,0 +1,4 @@
+MRuby::Gem::Specification.new('keyword_arguments_example') do |spec|
+  spec.license = 'MIT'
+  spec.author  = 'Tradam'
+end
diff --git a/mrb_gems/keyword_arguments_example/src/keyword_arguments_example.c b/mrb_gems/keyword_arguments_example/src/keyword_arguments_example.c
new file mode 100644
index 0000000..c90b507
--- /dev/null
+++ b/mrb_gems/keyword_arguments_example/src/keyword_arguments_example.c
@@ -0,0 +1,66 @@
+#include <mruby.h>
+#include <stdio.h>
+
+// defining the function to be later bound to a ruby method
+static mrb_value
+multiply_numbers(mrb_state *mrb, mrb_value self)
+{
+	// the number of keyword arguments we expect
+	uint32_t kw_num = 2;
+
+	const mrb_sym kw_names[] = {	// the array where we specify what we expect the keyword arguments to be named
+		mrb_intern_lit(mrb, "x"),	// we will expect an 'x' keyword
+		mrb_intern_lit(mrb, "y"),	// we will expect a 'y' keyword
+	};
+
+	// initialize the array where the values of they kwargs will be temporarily stored
+	mrb_value kw_values[kw_num];
+
+	// When getting arguments, the function expects all the data we
+	// created above to be formatted into a specific struct. So we
+	// create this struct here.
+	const mrb_kwargs kwargs = {
+		kw_num,		// number of kwargs
+		0,			// number of required kwargs
+		kw_names,	// names of kwargs
+		kw_values,	// values of kwargs(will be filled out)
+		NULL		// remaining kwargs(NULL specifies to error if other kwargs or args are given)
+	};
+
+	mrb_get_args(mrb, "|:", &kwargs); // get the arguments
+
+	if (mrb_undef_p(kw_values[0])){ // check if we actually recieved the first kwarg
+		kw_values[0] = mrb_fixnum_value(5); // set a default  value if we didnt
+		// notice that because kw_values only holds ruby objects
+		// we must convert the number "5" into a ruby object by
+		// using the 'mrb_fixnum_value' function
+	}
+
+	if (mrb_undef_p(kw_values[1])){ // ditto with second kwarg
+		kw_values[1] = mrb_fixnum_value(5);
+	}
+
+	// we convert the ruby objects back into C
+	// ints, mutiply them and then return the
+	// value as a ruby object
+	return mrb_fixnum_value(mrb_as_int(mrb,kw_values[0]) * mrb_as_int(mrb,kw_values[1]));
+}
+
+// gem initializer
+void
+mrb_keyword_arguments_example_gem_init(mrb_state* mrb) {
+	struct RClass *keyword_arguments_example_class = mrb_define_module(mrb, "KeywordArgumentsExample");
+	mrb_define_class_method(
+			mrb,                    // Mruby VM state
+			keyword_arguments_example_class,  // Class we bind method to
+			"multiply_numbers",            // Name of method
+			multiply_numbers,        // Function we are binding as a method
+			MRB_ARGS_ANY()	         // How many arguments are optional/required
+			);
+}
+
+// gem finalizer
+void
+mrb_keyword_arguments_example_gem_final(mrb_state* mrb) {
+
+}
diff --git a/test_suite.rb b/test_suite.rb
index 7ddc1eb..5ceb936 100644
--- a/test_suite.rb
+++ b/test_suite.rb
@@ -6,9 +6,14 @@ BasicExample.say_hello
 BasicExample.say_goodbye
 puts
 
-puts " - Multiply Numbers Return Example - "
+puts " - Arguments And Return Example - "
 print "3 * 10 = "
 puts ArgumentsAndReturnExample.multiply_numbers(3, 10)
 puts
 
+puts " - Keyword Arguments Example - "
+print "(x: 4) * (y: 6) = "
+puts KeywordArgumentsExample.multiply_numbers(x: 4, y: 6)
+puts
+
 puts "Reached end of test suite."