diff --git a/src/AnsiColor.jl b/src/AnsiColor.jl
index 724adfe..801aa84 100644
--- a/src/AnsiColor.jl
+++ b/src/AnsiColor.jl
@@ -1,7 +1,7 @@
 module AnsiColor
 export colorize, black, red, green, yellow, blue, magenta, cyan, white, uncolor
 
-COLORS = {
+COLORS = Dict(
   "black"          => 0,
   "red"            => 1,
   "green"          => 2,
@@ -20,46 +20,43 @@ COLORS = {
   "light_magenta"  => 65,
   "light_cyan"     => 66,
   "light_white"    => 67
-  }
+  )
 
-MODES = {
+MODES = Dict(
   "default"        => 0,
   "bold"           => 1,
   "underline"      => 4,
   "blink"          => 5,
   "swap"           => 7,
   "hide"           => 8
-  }
+  )
 
 COLOR_OFFSET       = 30
 BACKGROUND_OFFSET  = 40
 
-function colorize(color::String, str::String; background::String = "default", mode::String="default")
+colorize(color::AbstractString, str::AbstractString; background::AbstractString = "default", mode::AbstractString="default") =
   "\033[$(MODES[mode]);$(COLOR_OFFSET + COLORS[color]);$(BACKGROUND_OFFSET + COLORS[background])m$(str)\033[0m"
-end
 
-function colorize(color::Symbol, str::String; background::String = "default", mode::String="default")
+colorize(color::Symbol, str::AbstractString; background::AbstractString = "default", mode::AbstractString="default") =
   colorize(string(color), str; background=background, mode=mode)
-end
 
-black(str::String)    = colorize(:black, str)
-red(str::String)      = colorize(:red, str)
-green(str::String)    = colorize(:green, str)
-yellow(str::String)   = colorize(:yellow, str)
-blue(str::String)     = colorize(:blue, str)
-magenta(str::String)  = colorize(:magenta, str)
-cyan(str::String)     = colorize(:cyan, str)
-white(str::String)    = colorize(:white, str)
-uncolor(str::String)  = colorize(:default, str)
-
-light_black(str::String)    = colorize(:light_black, str)
-light_red(str::String)      = colorize(:light_red, str)
-light_green(str::String)    = colorize(:light_green, str)
-light_yellow(str::String)   = colorize(:light_yellow, str)
-light_blue(str::String)     = colorize(:light_blue, str)
-light_magenta(str::String)  = colorize(:light_magenta, str)
-light_cyan(str::String)     = colorize(:light_cyan, str)
-light_white(str::String)    = colorize(:light_white, str)
+black(str::AbstractString)    = colorize(:black, str)
+red(str::AbstractString)      = colorize(:red, str)
+green(str::AbstractString)    = colorize(:green, str)
+yellow(str::AbstractString)   = colorize(:yellow, str)
+blue(str::AbstractString)     = colorize(:blue, str)
+magenta(str::AbstractString)  = colorize(:magenta, str)
+cyan(str::AbstractString)     = colorize(:cyan, str)
+white(str::AbstractString)    = colorize(:white, str)
+uncolor(str::AbstractString)  = colorize(:default, str)
+
+light_black(str::AbstractString)    = colorize(:light_black, str)
+light_red(str::AbstractString)      = colorize(:light_red, str)
+light_green(str::AbstractString)    = colorize(:light_green, str)
+light_yellow(str::AbstractString)   = colorize(:light_yellow, str)
+light_blue(str::AbstractString)     = colorize(:light_blue, str)
+light_magenta(str::AbstractString)  = colorize(:light_magenta, str)
+light_cyan(str::AbstractString)     = colorize(:light_cyan, str)
+light_white(str::AbstractString)    = colorize(:light_white, str)
 
 end
-