Added bind function

README.md

@@ -614,6 +614,20 @@ _.each(notes, function(note)
 end)
 ```
 
+## bind
+
+`_.bind(function, table)`
+
+Bind a function to a table, meaning that whenever the function is called, the value of self will be the table. 
+
+```lua
+local func = function(self, greeting) return greeting .. ': ' .. self.name end
+func = _.bind(func, {name = 'moe'})
+func('hi')
+=> 'hi: moe'
+```
+
+
 ## wrap
 
 `_.wrap(function, wrapper)`

lib/underscore.lua

@@ -418,6 +418,12 @@ function _.after(times, func)
   end
 end
 
+function _.bind(func, object)
+  return function(...)
+    return func(object, ...)
+  end
+end
+
 function _.wrap(func, wrapper)
   return function(...)
     return wrapper(func, ...)

spec/functions_spec.lua

@@ -56,6 +56,15 @@ describe("#after", function()
   end)
 end)
 
+describe("#bind", function()
+  local table = {name = "moe"}
+  local greet = function(self) return "hi: " .. self.name end
+  it("returns a closure that binds a function to a table scope ", function()
+    local binded = _.bind(greet, table)
+    assert.equals(binded(), "hi: moe")
+  end)
+end)
+
 describe("#wrap", function()
   it("passes arguments ", function()
     local greet = function(name) return "hi: " .. name end