Improve README and build info.

COPYING

@@ -0,0 +1,19 @@
+Chain Copyright (c) 2016 Erik Osheim.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+of the Software, and to permit persons to whom the Software is furnished to do
+so, subject to the following conditions: 
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software. 
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE. 

README.md

@@ -2,12 +2,12 @@
 
 ### Dedication
 
-> all day long they work so hard / 'til the sun is going down
-> working on the highways and byways / and wearing, wearing a frown
-> you hear them moaning their lives away / then you hear somebody say:
+> all day long they work so hard / 'til the sun is going down /
+> working on the highways and byways / and wearing, wearing a frown /
+> you hear them moaning their lives away / then you hear somebody say: /
 >
-> that's the sound of the men / working on the chain gang
-> that's the sound of the men / working on the chain gang
+> that's the sound of the men / working on the chain gang /
+> that's the sound of the men / working on the chain gang /
 >
 > --Sam Cooke, "Chain Gang" (1960)
 
@@ -61,16 +61,29 @@ libraryDependencies += "org.spire-math" %%% "chain" % "0.1.0"
 ### Details
 
 Chain can wrap any `Iterable[A]` values, and support concatenation
-between mixed collection types:
+between mixed collection types. Here's an example that shows off a
+number of Chain's capabilities:
 
 ```scala
 import chain.Chain
 
-val xs: List[Int] = ...
-val ys: Vector[Int] = ...
-val zs: Option[Int] = ...
-
-val c = Chain(xs) ++ Chain(ys) ++ Chain(zs)
+val ws: Iterable[Int] = List(1,2,3)
+val xs: List[Int] = List(4,5,6)
+val ys: Vector[Int] = Vector(7,8,9,10,11)
+val zs: Option[Int] = Some(12)
+
+val a = Chain(ws) ++ Chain(xs) // no copying
+val b = Chain.all(ys, zs)      // same as ys ++ zs
+val c = 9 +: (a ++ b) :+ 100   // supports prepend/append
+
+c.toVector           // Vector(1,2,3,4,5,6,7,8,9,10,11,12)
+c.iterator.toList    // List(1,2,3,4,5,6,7,8,9,10,11,12)
+c.foreach(println)   // prints 1-12
+c.find(_ > 6)        // Some(7)
+c.forall(_ >= 0)     // true
+c.exists(_ > 100)    // false
+c.map(_ * 2)         // Chain(2,4,6,8,10,12,14,16,18,20,22,24)
+c.filter(_ % 3 == 0) // Chain(3,6,9,12)
 ```
 
 Chain is sealed and consists of two concrete case classes:
@@ -85,6 +98,15 @@ efficiently walk the contents in O(n) time.
 
 Concatenating chains is always O(1), and iteration is always O(n).
 
+Empty Chains can be obtained by `Chain.empty[A]` and are represented
+as a singleton `Chain.Empty` which is a `Chain(Nil)`. This value is
+immutable and can be shared safely. Chains with a single element are
+constructed by `Chain.single(x)` which constructs `Chain(x :: Nil)`
+instances. This is done transparently in the case of `+:` and `:+`.
+These encoding are relatively efficient although if you are working
+entirely with single elements a more efficient data structure is
+possible.
+
 Some operations that transform the Chain will need to allocate a new
 collection (either directly, or wrapped in a new `Chain[A]`). The
 comments explain the exact performance characteristics of each method,
@@ -136,7 +158,9 @@ towards supporting large collections.
 
 As mentioned above, it would be great to have a story for using type
 classes instead of `Iterable[A]` (either via an abstraction or a new
-type).
+type). It could also be nice to have a version which supported lazy
+filtering/mapping (although in many cases this can be emulated with
+things like `.iterator.filter`).
 
 ### Copyright and License
 

build.sbt

@@ -3,7 +3,7 @@ import ReleaseTransformations._
 lazy val chainSettings = Seq(
   organization := "org.spire-math",
   licenses += ("MIT", url("http://opensource.org/licenses/MIT")),
-  homepage := Some(url("http://github.com/striation/chain")),
+  homepage := Some(url("http://github.com/non/chain")),
   scalaVersion := "2.11.8",
   crossScalaVersions := Seq("2.10.6", "2.11.8"),
   scalacOptions ++= Seq(
@@ -26,14 +26,14 @@ lazy val chainSettings = Seq(
   },
   pomExtra := (
     <scm>
-      <url>git@github.com:striation/chain.git</url>
-      <connection>scm:git:git@github.com:striation/chain.git</connection>
+      <url>git@github.com:non/chain.git</url>
+      <connection>scm:git:git@github.com:non/chain.git</connection>
     </scm>
     <developers>
       <developer>
-        <id>striation</id>
+        <id>non</id>
         <name>Erik Osheim</name>
-        <url>http://github.com/striation/</url>
+        <url>http://github.com/non/</url>
       </developer>
     </developers>
   ),