1 files changed, 93 insertions, 0 deletions
diff --git a/mrblib/string.rb b/mrblib/string.rb
new file mode 100644
index 000000000..78f2bea9d
--- /dev/null
+++ b/mrblib/string.rb
@@ -0,0 +1,93 @@
+#
+#  String
+#
+class String
+  # 15.2.10.5.15
+  def each_line(&block)
+    # expect that str.index accepts an Integer for 1st argument as a byte data
+    offset = 0
+    while(pos = self.index(0x0a, offset))
+      block.call(self[offset, pos + 1 - offset])
+      offset = pos + 1
+    end
+    block.call(self[offset, self.size - offset]) if self.size > offset
+    self
+  end
+
+  # 15.2.10.5.18
+  def gsub(*args, &block)
+    unless (args.size == 1 && block) || args.size == 2
+      raise ArgumentError, "wrong number of arguments"
+    end
+
+    ### *** TODO *** ###
+  end
+
+  # 15.2.10.5.19
+  def gsub!(*args, &block)
+    str = self.gsub(*args, &block)
+    if str != self
+      self.replace(str)
+      self
+    else
+      nil
+    end
+  end
+
+  # 15.2.10.5.32
+  def scan(reg, &block)
+    ### *** TODO *** ###
+  end
+
+  # 15.2.10.5.36
+  def sub(*args, &block)
+    unless (args.size == 1 && block) || args.size == 2
+      raise ArgumentError, "wrong number of arguments"
+    end
+
+    ### *** TODO *** ###
+  end
+
+  # 15.2.10.5.37
+  def sub!(*args, &block)
+    str = self.sub(*args, &block)
+    if str != self
+      self.replace(str)
+      self
+    else
+      nil
+    end
+  end
+
+  def each_char(&block)
+    pos = 0
+    while(pos < self.size)
+      block.call(self[pos])
+      pos += 1
+    end
+    self
+  end
+
+  def each_byte(&block)
+    bytes = self.unpack("C*")
+    pos = 0
+    while(pos < bytes.size)
+      block.call(bytes[pos])
+      pos += 1
+    end
+    self
+  end
+
+  def []=(pos, value)
+    b = self[0, pos]
+    a = self[pos+1..-1]
+    p [b, value, a].join('')
+    self.replace([b, value, a].join(''))
+  end
+end
+
+# include modules
+module Comparable; end
+class String
+  include Comparable
+end