Merge pull request #507 from kostya/first

Enumerable#first

lib-topaz/array.rb

@@ -137,8 +137,12 @@ def delete(obj, &block)
     return nil
   end
 
-  def first
-    return self[0]
+  def first(*args)
+    if args.empty?
+      self[0]
+    else
+      take(*args)
+    end
   end
 
   def flatten(level = -1)

lib-topaz/enumerable.rb

@@ -1,4 +1,14 @@
 module Enumerable
+
+  def first(*args)
+    if args.empty?
+      self.each { |e| return e }
+      nil
+    else
+      take(*args)
+    end
+  end
+
   def map
     result = []
     self.each do |x|
@@ -95,6 +105,7 @@ def detect(ifnone = nil, &block)
   alias find detect
 
   def take(n)
+    n = Topaz.coerce_int(n)
     raise ArgumentError.new("attempt to take negative size") if n < 0
     result = []
     unless n == 0

lib-topaz/range.rb

@@ -21,6 +21,14 @@ def each(&block)
     self
   end
 
+  def first(*args)
+    if args.empty?
+      self.begin
+    else
+      take(*args)
+    end
+  end
+
   def ===(value)
     self.include?(value)
   end

spec/tags/core/array/first_tags.txt

@@ -1,11 +0,0 @@
-fails:Array#first returns the first count elements if given a count
-fails:Array#first returns an empty array when passed count on an empty array
-fails:Array#first returns an empty array when passed count == 0
-fails:Array#first returns an array containing the first element when passed count == 1
-fails:Array#first returns the entire array when count > length
-fails:Array#first returns an array which is independent to the original when passed count
-fails:Array#first tries to convert the passed argument to an Integer using #to_int
-fails:Array#first raises a TypeError if the passed argument is not numeric
-fails:Array#first does not return subclass instance when passed count on Array subclasses
-fails:Array#first is not destructive
-fails:Array#first 

spec/tags/core/enumerable/first_tags.txt

@@ -1,12 +1 @@
-fails:Enumerable#first returns the first element
-fails:Enumerable#first returns nil if self is empty
-fails:Enumerable#first when passed an argument returns the first count elements if given a count
-fails:Enumerable#first when passed an argument returns an empty array when passed count on an empty array
-fails:Enumerable#first when passed an argument returns an empty array when passed count == 0
-fails:Enumerable#first when passed an argument returns an array containing the first element when passed count == 1
-fails:Enumerable#first when passed an argument raises an ArgumentError when count is negative
-fails:Enumerable#first when passed an argument returns the entire array when count > length
-fails:Enumerable#first when passed an argument tries to convert the passed argument to an Integer using #to_int
-fails:Enumerable#first when passed an argument raises a TypeError if the passed argument is not numeric
 fails:Enumerable#first when passed an argument gathers whole arrays as elements when each yields multiple
-fails:Enumerable#first when passed an argument consumes only what is needed

spec/tags/core/enumerable/take_tags.txt

@@ -1,3 +1 @@
-fails:Enumerable#take when passed an argument tries to convert the passed argument to an Integer using #to_int
-fails:Enumerable#take when passed an argument raises a TypeError if the passed argument is not numeric
 fails:Enumerable#take when passed an argument gathers whole arrays as elements when each yields multiple

topaz/modules/topaz.py

@@ -15,3 +15,7 @@ def method_intmask(self, space, w_int):
         elif space.is_kind_of(w_int, space.w_bignum):
             bigint = space.bigint_w(w_int)
             return space.newint(intmask(bigint.uintmask()))
+
+    @moduledef.function("coerce_int")
+    def method_coerce_int(self, space, w_obj):
+        return space.convert_type(w_obj, space.w_fixnum, "to_int")

topaz/objects/rangeobject.py

@@ -28,7 +28,6 @@ def method_initialize(self, space, w_start, w_end, excl=False):
         self.w_end = w_end
         self.exclusive = excl
 
-    @classdef.method("first")
     @classdef.method("begin")
     def method_begin(self, space):
         return self.w_start