lib/susy/sass_extensions.rb in compass-susy-plugin-0.7.0.pre1 vs lib/susy/sass_extensions.rb in compass-susy-plugin-0.7.0.pre2

@@ -1,79 +1,68 @@
 require 'sass'
 
 module Sass::Script::Functions
-  # set the Susy base font size (in pixels)
-  # return the percentage base font size
-  #  this could be done in Sass, but we need to store the px_size so we
-  #  can provide a px_to_em function
-  def base_font_size(base_font_size_px)
-    @@susy_base_font_size_px = Float(base_font_size_px.value)
-    Sass::Script::Number.new((@@susy_base_font_size_px / 16) * 100)
-  end
 
-  # approximate a given pixel size in ems
-  def px2em(size_in_px)
-    Sass::Script::Number.new((size_in_px.value / @@susy_base_font_size_px))
-  end
+  # some helpful constants
+  PERCENT = Sass::Script::Number.new(100, ["%"])
+  ONE = Sass::Script::Number.new(1)
+  TWO = Sass::Script::Number.new(2)
 
   # set the Susy column and gutter widths and number of columns
-  #  column, gutter and padding widths should be sent as unitless numbers, 
-  #  though they may "really" be ems or pixels (_grid.sass handles units).
-  # return total width of container (without units)
+  # return total width of container
   def container(total_columns, column_width, gutter_width, side_gutter_width)
-    @@susy_total_columns = total_columns.value
-    @@susy_column_width = Float(column_width.value)
-    @@susy_gutter_width = Float(gutter_width.value)
-    @@susy_side_gutter_width = Float(side_gutter_width.value)
+    @@susy_total_columns = total_columns
+    @@susy_column_width = column_width
+    @@susy_gutter_width = gutter_width
+    @@susy_side_gutter_width = side_gutter_width
     context
   end
 
   # return the width of 'n' columns plus 'n - 1' gutters 
   # plus page padding in non-nested contexts
-  def context(n = nil)
-    begin
-      n = n.value
-    rescue NoMethodError
-      n = false
-    end
-    sg = 0
-    if !n
+  def context(n = false)
+    raise Sass::SyntaxError, "container() must be called before context() - should be called in susy/susy.sass" unless defined?(@@susy_total_columns)
+    sg = Sass::Script::Number.new(0)
+    if !n or !n.value
       n = @@susy_total_columns
       sg = @@susy_side_gutter_width
     end
     c, g = [@@susy_column_width, @@susy_gutter_width]
-    Sass::Script::Number.new(((n * c) + ((n - 1) * g)) + (sg * 2))
+    n.times(c).plus(n.minus(ONE).times(g)).plus(sg.times(TWO))
   end
 
-  # return the percentage width of 'number' columns in a context of
+  # return the percentage width of 'n' columns in a context of
   #  'context_columns'
-  def columns(number, context_columns = nil)
-    n = number.value
-    context_width = context(context_columns).value
+  def columns(n, context_columns = false)
+    raise Sass::SyntaxError, "container() must be called before columns() - should be called in susy/susy.sass" unless defined?(@@susy_column_width)
+    w = context(context_columns)
     c, g = [@@susy_column_width, @@susy_gutter_width]
-    Sass::Script::Number.new((((n * c) + ((n - 1) * g)) / context_width) * 100)
+    n.times(c).plus(n.minus(ONE).times(g)).div(w).times(PERCENT)
   end
 
   # return the percentage width of a single gutter in a context of
   #  'context_columns'
-  def gutter(context_columns = nil)
-    context_width = context(context_columns).value
+  def gutter(context_columns = false)
+    raise Sass::SyntaxError, "container() must be called before columns() - should be called in susy/susy.sass" unless defined?(@@susy_gutter_width)
+    w = context(context_columns)
     g = @@susy_gutter_width
-    Sass::Script::Number.new((g / context_width) * 100)
+    g.div(w).times(PERCENT)
   end
 
   # return the percentage width of a single side gutter in a context of
   #  'context_columns'
-  def side_gutter(context_columns = nil)
-    context_width = context(context_columns).value
+  def side_gutter(context_columns = false)
+    raise Sass::SyntaxError, "container() must be called before side_gutter() - should be called in susy/susy.sass" unless defined?(@@susy_side_gutter_width)
+    w = context(context_columns)
     sg = @@susy_side_gutter_width
-    Sass::Script::Number.new((sg / context_width) * 100)
+    sg.div(w).times(PERCENT)
   end
 
   # return the percentage width of a single column in a context of
   #  'context_columns'
-  def column(context_columns = nil)
-    context_width = context(context_columns).value
+  def column(context_columns = false)
+    raise Sass::SyntaxError, "container() must be called before column() - should be called in susy/susy.sass" unless defined?(@@susy_column_width)
+    w = context(context_columns)
     c = @@susy_column_width
-    Sass::Script::Number.new((c / context_width) * 100)
+    c.div(w).times(PERCENT)
   end
 end