ADDED   src/0dev.org/bits/bits.go
Index: src/0dev.org/bits/bits.go
==================================================================
--- src/0dev.org/bits/bits.go
+++ src/0dev.org/bits/bits.go
@@ -0,0 +1,92 @@
+// Package bits provides a bit vector backed with uints
+package bits
+
+import (
+	"strconv"
+)
+
+// The Vector interface defines methods on the bit vector
+type Vector interface {
+	// Retrieves the bit at the designated position
+	Peek(uint) bool
+	// Sets the bit at the designated position
+	Poke(uint, bool)
+	// Flips the bit at the designated position
+	Flip(uint)
+	// Returns the total number of elements supported by the vector
+	Len() uint
+}
+
+type boolvector []bool
+
+// Retrieves the bit at the designated position
+func (v boolvector) Peek(pos uint) bool {
+	return v[pos]
+}
+
+// Sets the bit at the designated position
+func (v boolvector) Poke(pos uint, val bool) {
+	v[pos] = val
+}
+
+// Flips the bit at the designated position
+func (v boolvector) Flip(pos uint) {
+	v[pos] = !v[pos]
+}
+
+// Returns the total number of elements supported by the vector
+func (v boolvector) Len() uint {
+	return uint(len(v))
+}
+
+type vector []uint
+
+// Retrieves the bit at the designated position
+func (v vector) Peek(pos uint) bool {
+	var slot, offset uint = at(pos)
+	return (v[slot] & (1 << offset)) > 0
+}
+
+// Sets the bit at the designated position
+func (v vector) Poke(pos uint, val bool) {
+	var slot, offset uint = at(pos)
+	if val {
+		v[slot] |= (1 << offset)
+	} else {
+		v[slot] &^= (1 << offset)
+	}
+}
+
+// Flips the bit at the designated position
+func (v vector) Flip(pos uint) {
+	var slot, offset uint = at(pos)
+	v[slot] ^= (1 << offset)
+}
+
+// Returns the total number of elements supported by the vector
+func (v vector) Len() uint {
+	return uint(len(v) * strconv.IntSize)
+}
+
+func at(pos uint) (uint, uint) {
+	return pos / strconv.IntSize, pos % strconv.IntSize
+}
+
+// Create a new bit vector sized up to the desired number of elements
+func New(size uint) Vector {
+	var length uint = size / strconv.IntSize
+
+	if size%strconv.IntSize > 0 {
+		// Allocate one additional slot if the desired
+		// size is does not divide by 32/64
+		length++
+	}
+
+	var slice []uint = make([]uint, length)
+	return vector(slice)
+}
+
+func NewBool(size uint) Vector {
+	var slice []bool = make([]bool, size)
+	return boolvector(slice)
+}

ADDED   src/0dev.org/bits/bits_test.go
Index: src/0dev.org/bits/bits_test.go
==================================================================
--- src/0dev.org/bits/bits_test.go
+++ src/0dev.org/bits/bits_test.go
@@ -0,0 +1,65 @@
+package bits
+
+import (
+	"strconv"
+	"testing"
+)
+
+func TestSize(t *testing.T) {
+	sizes := []uint{0, 31, 32, 33, 61, 63, 64, 127, 128, 129}
+
+	for _, size := range sizes {
+		v := New(size)
+		if v.Len() < size || v.Len() > size+strconv.IntSize {
+			t.Error("Invalid length", v.Len(), "expected", size)
+		}
+	}
+}
+
+func TestEmpty(t *testing.T) {
+	var size uint = 128
+	v := New(size)
+
+	// Check if it is empty by default
+	for i := uint(0); i < size; i++ {
+		if v.Peek(i) {
+			t.Error("Invalid raised bit at", i)
+		}
+	}
+}
+
+func TestBasic(t *testing.T) {
+	var size uint = 128
+	v := New(size)
+
+	// Raise and lower each position explicitly
+	for i := uint(0); i < size; i++ {
+		v.Poke(i, true)
+		if !v.Peek(i) {
+			t.Error("Invalid lowered bit at", i)
+		}
+
+		v.Poke(i, false)
+		if v.Peek(i) {
+			t.Error("Invalid raised bit at", i)
+		}
+	}
+}
+
+func TestFlip(t *testing.T) {
+	var size uint = 128
+	v := New(size)
+
+	// Raise and lower each position by flipping
+	for i := uint(0); i < size; i++ {
+		v.Flip(i)
+		if !v.Peek(i) {
+			t.Error("Invalid lowered bit at", i)
+		}
+
+		v.Flip(i)
+		if v.Peek(i) {
+			t.Error("Invalid raised bit at", i)
+		}
+	}
+}

ADDED   src/0dev.org/commands/plaindiff/main.go
Index: src/0dev.org/commands/plaindiff/main.go
==================================================================
--- src/0dev.org/commands/plaindiff/main.go
+++ src/0dev.org/commands/plaindiff/main.go
@@ -0,0 +1,165 @@
+package main
+
+import (
+	diff "0dev.org/diff"
+	"bufio"
+	"flag"
+	"fmt"
+	"hash"
+	"hash/fnv"
+	"io"
+	"os"
+)
+
+const usage = "Usage: plaindiff <file1> <file2>"
+
+func main() {
+	flag.Parse()
+
+	var args []string = flag.Args()
+	if len(args) != 2 {
+		os.Stderr.WriteString(usage)
+		os.Exit(1)
+	}
+
+	var hd hashDiff
+	hd.hash = fnv.New64a()
+	hd.first = read(args[0], hd.hash)
+	hd.second = read(args[1], hd.hash)
+
+	var result diff.Delta = diff.Diff(&hd)
+	//var marks []diff.Mark = make([]diff.Mark, len(result.Added)+len(result.Removed))
+
+	//var added, removed []diff.Mark = result.Added, result.Removed
+	fmt.Println(result)
+
+	gen := source(result)
+	for have, added, mark := gen(); have; have, added, mark = gen() {
+		var from []line
+		if added {
+			from = hd.second
+		} else {
+			from = hd.first
+		}
+
+		fmt.Println()
+		for i := mark.From; i < mark.Length; i++ {
+			fmt.Print(i)
+			if added {
+				fmt.Print(" > ")
+			} else {
+				fmt.Print(" < ")
+			}
+			fmt.Println(from[i].text)
+		}
+	}
+
+}
+
+func source(d diff.Delta) func() (bool, bool, diff.Mark) {
+	var addedAt, removedAt int = 0, 0
+	return func() (bool, bool, diff.Mark) {
+		var addsOver bool = addedAt == len(d.Added)
+		var removesOver bool = removedAt == len(d.Removed)
+
+		var add, remove diff.Mark
+
+		// Check whether both mark slices have been exhausted
+		if addsOver && removesOver {
+			return false, false, diff.Mark{}
+		}
+
+		// Return an add if removes are over
+		if removesOver {
+			add = d.Added[addedAt]
+			addedAt++
+			return true, true, add
+		}
+
+		// Return a remove if the adds are over
+		if addsOver {
+			remove = d.Removed[removedAt]
+			removedAt++
+			return true, false, remove
+		}
+
+		add = d.Added[addedAt]
+		remove = d.Removed[removedAt]
+
+		// Prioritize a remove if it happens before an add
+		if remove.From <= add.From {
+			removedAt++
+			return true, false, remove
+		}
+
+		// Else
+		addedAt++
+		return true, true, add
+
+	}
+}
+
+// A line-based diff.Interface implementation
+type hashDiff struct {
+	first, second []line
+	hash          hash.Hash64
+}
+
+func (h *hashDiff) Equal(i, j int) bool {
+	// return h.first[i].text == h.second[j].text
+	if h.first[i].hash != h.second[j].hash {
+		return false
+	} else {
+		return h.first[i].text == h.second[j].text
+	}
+}
+
+func (h *hashDiff) Len() (int, int) {
+	return len(h.first), len(h.second)
+}
+
+type line struct {
+	hash uint64
+	text string
+}
+
+// Reads all lines in a file and returns a line entry for each
+func read(name string, h hash.Hash64) []line {
+	var f *os.File
+	var e error
+
+	f, e = os.Open(name)
+	fatal(e)
+
+	var result []line = lines(f, h)
+	fatal(f.Close())
+
+	return result
+}
+
+// Reads all lines and returns a line entry for each
+func lines(r io.Reader, h hash.Hash64) []line {
+	var scanner *bufio.Scanner = bufio.NewScanner(r)
+	var result []line = make([]line, 0)
+	for scanner.Scan() {
+		h.Reset()
+		h.Write(scanner.Bytes())
+		result = append(result, line{hash: h.Sum64(), text: scanner.Text()})
+	}
+	return result
+}
+
+// Write an error to stderr
+func stderr(e error) {
+	if e != nil {
+		os.Stderr.WriteString(e.Error())
+	}
+}
+
+// Write an error to stderr and exit
+func fatal(e error) {
+	if e != nil {
+		stderr(e)
+		os.Exit(1)
+	}
+}

ADDED   src/0dev.org/commands/plaindiff/rime1.txt
Index: src/0dev.org/commands/plaindiff/rime1.txt
==================================================================
--- src/0dev.org/commands/plaindiff/rime1.txt
+++ src/0dev.org/commands/plaindiff/rime1.txt
@@ -0,0 +1,780 @@
+It is an ancient Mariner,
+And he stoppeth one of three.
+'By thy long grey beard and glittering eye,
+Now wherefore stopp'st thou me?
+
+The Bridegroom's doors are opened wide,
+And I am next of kin;
+The guests are met, the feast is set:
+May'st hear the merry din.'
+
+He holds him with his skinny hand,
+'There was a ship,' quoth he.
+'Hold off! unhand me, grey-beard loon!'
+Eftsoons his hand dropt he.
+
+He holds him with his glittering eye—
+The Wedding-Guest stood still,
+And listens like a three years' child:
+The Mariner hath his will.
+
+The Wedding-Guest sat on a stone:
+He cannot choose but hear;
+And thus spake on that ancient man,
+The bright-eyed Mariner.
+
+'The ship was cheered, the harbour cleared,
+Merrily did we drop
+Below the kirk, below the hill,
+Below the lighthouse top.
+
+The Sun came up upon the left,
+Out of the sea came he!
+And he shone bright, and on the right
+Went down into the sea.
+
+Higher and higher every day,
+Till over the mast at noon—'
+The Wedding-Guest here beat his breast,
+For he heard the loud bassoon.
+
+The bride hath paced into the hall,
+Red as a rose is she;
+Nodding their heads before her goes
+The merry minstrelsy.
+
+The Wedding-Guest he beat his breast,
+Yet he cannot choose but hear;
+And thus spake on that ancient man,
+The bright-eyed Mariner.
+
+And now the STORM-BLAST came, and he
+Was tyrannous and strong:
+He struck with his o'ertaking wings,
+And chased us south along.
+
+With sloping masts and dipping prow,
+As who pursued with yell and blow
+Still treads the shadow of his foe,
+And forward bends his head,
+The ship drove fast, loud roared the blast,
+And southward aye we fled.
+
+And now there came both mist and snow,
+And it grew wondrous cold:
+And ice, mast-high, came floating by,
+As green as emerald.
+
+And through the drifts the snowy clifts
+Did send a dismal sheen:
+Nor shapes of men nor beasts we ken—
+The ice was all between.
+
+The ice was here, the ice was there,
+The ice was all around:
+It cracked and growled, and roared and howled,
+Like noises in a swound!
+
+At length did cross an Albatross,
+Thorough the fog it came;
+As if it had been a Christian soul,
+We hailed it in God's name.
+
+It ate the food it ne'er had eat,
+And round and round it flew.
+The ice did split with a thunder-fit;
+The helmsman steered us through!
+
+And a good south wind sprung up behind;
+The Albatross did follow,
+And every day, for food or play,
+Came to the mariner's hollo!
+
+In mist or cloud, on mast or shroud,
+It perched for vespers nine;
+Whiles all the night, through fog-smoke white,
+Glimmered the white Moon-shine.'
+
+'God save thee, ancient Mariner!
+From the fiends, that plague thee thus!—
+Why look'st thou so?'—With my cross-bow
+I shot the ALBATROSS.
+
+PART II
+The Sun now rose upon the right:
+Out of the sea came he,
+Still hid in mist, and on the left
+Went down into the sea.
+
+And the good south wind still blew behind,
+But no sweet bird did follow,
+Nor any day for food or play
+Came to the mariner's hollo!
+
+And I had done a hellish thing,
+And it would work 'em woe:
+For all averred, I had killed the bird
+That made the breeze to blow.
+Ah wretch! said they, the bird to slay,
+That made the breeze to blow!
+
+Nor dim nor red, like God's own head,
+The glorious Sun uprist:
+Then all averred, I had killed the bird
+That brought the fog and mist.
+'Twas right, said they, such birds to slay,
+That bring the fog and mist.
+
+The fair breeze blew, the white foam flew,
+The furrow followed free;
+We were the first that ever burst
+Into that silent sea.
+
+Down dropt the breeze, the sails dropt down,
+'Twas sad as sad could be;
+And we did speak only to break
+The silence of the sea!
+
+All in a hot and copper sky,
+The bloody Sun, at noon,
+Right up above the mast did stand,
+No bigger than the Moon.
+
+Day after day, day after day,
+We stuck, nor breath nor motion;
+As idle as a painted ship
+Upon a painted ocean.
+
+Water, water, every where,
+And all the boards did shrink;
+Water, water, every where,
+Nor any drop to drink.
+
+The very deep did rot: O Christ!
+That ever this should be!
+Yea, slimy things did crawl with legs
+Upon the slimy sea.
+
+About, about, in reel and rout
+The death-fires danced at night;
+The water, like a witch's oils,
+Burnt green, and blue and white.
+
+And some in dreams assurèd were
+Of the Spirit that plagued us so;
+Nine fathom deep he had followed us
+From the land of mist and snow.
+
+And every tongue, through utter drought,
+Was withered at the root;
+We could not speak, no more than if
+We had been choked with soot.
+
+Ah! well a-day! what evil looks
+Had I from old and young!
+Instead of the cross, the Albatross
+About my neck was hung.
+
+PART III
+There passed a weary time. Each throat
+Was parched, and glazed each eye.
+A weary time! a weary time!
+How glazed each weary eye,
+
+When looking westward, I beheld
+A something in the sky.
+
+At first it seemed a little speck,
+And then it seemed a mist;
+It moved and moved, and took at last
+A certain shape, I wist.
+
+A speck, a mist, a shape, I wist!
+And still it neared and neared:
+As if it dodged a water-sprite,
+It plunged and tacked and veered.
+
+With throats unslaked, with black lips baked,
+We could nor laugh nor wail;
+Through utter drought all dumb we stood!
+I bit my arm, I sucked the blood,
+And cried, A sail! a sail!
+
+With throats unslaked, with black lips baked,
+Agape they heard me call:
+Gramercy! they for joy did grin,
+And all at once their breath drew in.
+As they were drinking all.
+
+See! see! (I cried) she tacks no more!
+Hither to work us weal;
+Without a breeze, without a tide,
+She steadies with upright keel!
+
+The western wave was all a-flame.
+The day was well nigh done!
+Almost upon the western wave
+Rested the broad bright Sun;
+When that strange shape drove suddenly
+Betwixt us and the Sun.
+
+And straight the Sun was flecked with bars,
+(Heaven's Mother send us grace!)
+As if through a dungeon-grate he peered
+With broad and burning face.
+
+Alas! (thought I, and my heart beat loud)
+How fast she nears and nears!
+Are those her sails that glance in the Sun,
+Like restless gossameres?
+
+Are those her ribs through which the Sun
+Did peer, as through a grate?
+And is that Woman all her crew?
+Is that a DEATH? and are there two?
+Is DEATH that woman's mate?
+
+Her lips were red, her looks were free,
+Her locks were yellow as gold:
+Her skin was as white as leprosy,
+The Night-mare LIFE-IN-DEATH was she,
+Who thicks man's blood with cold.
+
+The naked hulk alongside came,
+And the twain were casting dice;
+'The game is done! I've won! I've won!'
+Quoth she, and whistles thrice.
+
+The Sun's rim dips; the stars rush out;
+At one stride comes the dark;
+With far-heard whisper, o'er the sea,
+Off shot the spectre-bark.
+
+We listened and looked sideways up!
+Fear at my heart, as at a cup,
+My life-blood seemed to sip!
+The stars were dim, and thick the night,
+The steersman's face by his lamp gleamed white;
+From the sails the dew did drip—
+Till clomb above the eastern bar
+The hornèd Moon, with one bright star
+Within the nether tip.
+
+One after one, by the star-dogged Moon,
+Too quick for groan or sigh,
+Each turned his face with a ghastly pang,
+And cursed me with his eye.
+
+Four times fifty living men,
+(And I heard nor sigh nor groan)
+With heavy thump, a lifeless lump,
+They dropped down one by one.
+
+The souls did from their bodies fly,—
+They fled to bliss or woe!
+And every soul, it passed me by,
+Like the whizz of my cross-bow!
+
+PART IV
+'I fear thee, ancient Mariner!
+I fear thy skinny hand!
+And thou art long, and lank, and brown,
+As is the ribbed sea-sand.
+
+I fear thee and thy glittering eye,
+And thy skinny hand, so brown.'—
+Fear not, fear not, thou Wedding-Guest!
+This body dropt not down.
+
+Alone, alone, all, all alone,
+Alone on a wide wide sea!
+And never a saint took pity on
+My soul in agony.
+
+The many men, so beautiful!
+And they all dead did lie:
+And a thousand thousand slimy things
+Lived on; and so did I.
+
+I looked upon the rotting sea,
+And drew my eyes away;
+I looked upon the rotting deck,
+And there the dead men lay.
+
+I looked to heaven, and tried to pray;
+But or ever a prayer had gusht,
+A wicked whisper came, and made
+My heart as dry as dust.
+
+I closed my lids, and kept them close,
+And the balls like pulses beat;
+For the sky and the sea, and the sea and the sky
+Lay dead like a load on my weary eye,
+And the dead were at my feet.
+
+The cold sweat melted from their limbs,
+Nor rot nor reek did they:
+The look with which they looked on me
+Had never passed away.
+
+An orphan's curse would drag to hell
+A spirit from on high;
+But oh! more horrible than that
+Is the curse in a dead man's eye!
+Seven days, seven nights, I saw that curse,
+And yet I could not die.
+
+The moving Moon went up the sky,
+And no where did abide:
+Softly she was going up,
+And a star or two beside—
+
+Her beams bemocked the sultry main,
+Like April hoar-frost spread;
+But where the ship's huge shadow lay,
+The charmèd water burnt alway
+A still and awful red.
+
+Beyond the shadow of the ship,
+I watched the water-snakes:
+They moved in tracks of shining white,
+And when they reared, the elfish light
+Fell off in hoary flakes.
+
+Within the shadow of the ship
+I watched their rich attire:
+Blue, glossy green, and velvet black,
+They coiled and swam; and every track
+Was a flash of golden fire.
+
+O happy living things! no tongue
+Their beauty might declare:
+A spring of love gushed from my heart,
+And I blessed them unaware:
+Sure my kind saint took pity on me,
+And I blessed them unaware.
+
+The self-same moment I could pray;
+And from my neck so free
+The Albatross fell off, and sank
+Like lead into the sea.
+
+PART V
+Oh sleep! it is a gentle thing,
+Beloved from pole to pole!
+To Mary Queen the praise be given!
+She sent the gentle sleep from Heaven,
+That slid into my soul.
+
+The silly buckets on the deck,
+That had so long remained,
+I dreamt that they were filled with dew;
+And when I awoke, it rained.
+
+My lips were wet, my throat was cold,
+My garments all were dank;
+Sure I had drunken in my dreams,
+And still my body drank.
+
+I moved, and could not feel my limbs:
+I was so light—almost
+I thought that I had died in sleep,
+And was a blessed ghost.
+
+And soon I heard a roaring wind:
+It did not come anear;
+But with its sound it shook the sails,
+That were so thin and sere.
+
+The upper air burst into life!
+And a hundred fire-flags sheen,
+To and fro they were hurried about!
+And to and fro, and in and out,
+The wan stars danced between.
+
+And the coming wind did roar more loud,
+And the sails did sigh like sedge,
+And the rain poured down from one black cloud;
+The Moon was at its edge.
+
+The thick black cloud was cleft, and still
+The Moon was at its side:
+Like waters shot from some high crag,
+The lightning fell with never a jag,
+A river steep and wide.
+
+The loud wind never reached the ship,
+Yet now the ship moved on!
+Beneath the lightning and the Moon
+The dead men gave a groan.
+
+They groaned, they stirred, they all uprose,
+Nor spake, nor moved their eyes;
+It had been strange, even in a dream,
+To have seen those dead men rise.
+
+The helmsman steered, the ship moved on;
+Yet never a breeze up-blew;
+The mariners all 'gan work the ropes,
+Where they were wont to do;
+They raised their limbs like lifeless tools—
+We were a ghastly crew.
+
+The body of my brother's son
+Stood by me, knee to knee:
+The body and I pulled at one rope,
+But he said nought to me.
+
+'I fear thee, ancient Mariner!'
+Be calm, thou Wedding-Guest!
+'Twas not those souls that fled in pain,
+Which to their corses came again,
+But a troop of spirits blest:
+
+For when it dawned—they dropped their arms,
+And clustered round the mast;
+Sweet sounds rose slowly through their mouths,
+And from their bodies passed.
+
+Around, around, flew each sweet sound,
+Then darted to the Sun;
+Slowly the sounds came back again,
+Now mixed, now one by one.
+
+Sometimes a-dropping from the sky
+I heard the sky-lark sing;
+Sometimes all little birds that are,
+How they seemed to fill the sea and air
+With their sweet jargoning!
+
+And now 'twas like all instruments,
+Now like a lonely flute;
+And now it is an angel's song,
+That makes the heavens be mute.
+
+It ceased; yet still the sails made on
+A pleasant noise till noon,
+A noise like of a hidden brook
+In the leafy month of June,
+That to the sleeping woods all night
+Singeth a quiet tune.
+
+Till noon we quietly sailed on,
+Yet never a breeze did breathe:
+Slowly and smoothly went the ship,
+Moved onward from beneath.
+
+Under the keel nine fathom deep,
+From the land of mist and snow,
+The spirit slid: and it was he
+That made the ship to go.
+The sails at noon left off their tune,
+And the ship stood still also.
+
+The Sun, right up above the mast,
+Had fixed her to the ocean:
+But in a minute she 'gan stir,
+With a short uneasy motion—
+Backwards and forwards half her length
+With a short uneasy motion.
+
+Then like a pawing horse let go,
+She made a sudden bound:
+It flung the blood into my head,
+And I fell down in a swound.
+
+How long in that same fit I lay,
+I have not to declare;
+But ere my living life returned,
+I heard and in my soul discerned
+Two voices in the air.
+
+'Is it he?' quoth one, 'Is this the man?
+By him who died on cross,
+With his cruel bow he laid full low
+The harmless Albatross.
+
+The spirit who bideth by himself
+In the land of mist and snow,
+He loved the bird that loved the man
+Who shot him with his bow.'
+
+The other was a softer voice,
+As soft as honey-dew:
+Quoth he, 'The man hath penance done,
+And penance more will do.'
+
+PART VI
+
+First Voice
+'But tell me, tell me! speak again,
+Thy soft response renewing—
+What makes that ship drive on so fast?
+What is the ocean doing?'
+
+Second Voice
+Still as a slave before his lord,
+The ocean hath no blast;
+His great bright eye most silently
+Up to the Moon is cast—
+
+If he may know which way to go;
+For she guides him smooth or grim.
+See, brother, see! how graciously
+She looketh down on him.'
+
+First Voice
+'But why drives on that ship so fast,
+Without or wave or wind?'
+
+Second Voice
+'The air is cut away before,
+And closes from behind.
+
+Fly, brother, fly! more high, more high!
+Or we shall be belated:
+For slow and slow that ship will go,
+When the Mariner's trance is abated.'
+
+I woke, and we were sailing on
+As in a gentle weather:
+'Twas night, calm night, the moon was high;
+The dead men stood together.
+
+All stood together on the deck,
+For a charnel-dungeon fitter:
+All fixed on me their stony eyes,
+That in the Moon did glitter.
+
+The pang, the curse, with which they died,
+Had never passed away:
+I could not draw my eyes from theirs,
+Nor turn them up to pray.
+
+And now this spell was snapt: once more
+I viewed the ocean green,
+And looked far forth, yet little saw
+Of what had else been seen—
+
+Like one, that on a lonesome road
+Doth walk in fear and dread,
+And having once turned round walks on,
+And turns no more his head;
+Because he knows, a frightful fiend
+Doth close behind him tread.
+
+But soon there breathed a wind on me,
+Nor sound nor motion made:
+Its path was not upon the sea,
+In ripple or in shade.
+
+It raised my hair, it fanned my cheek
+Like a meadow-gale of spring—
+It mingled strangely with my fears,
+Yet it felt like a welcoming.
+
+Swiftly, swiftly flew the ship,
+Yet she sailed softly too:
+Sweetly, sweetly blew the breeze—
+On me alone it blew.
+
+Oh! dream of joy! is this indeed
+The light-house top I see?
+Is this the hill? is this the kirk?
+Is this mine own countree?
+
+We drifted o'er the harbour-bar,
+And I with sobs did pray—
+O let me be awake, my God!
+Or let me sleep alway.
+
+The harbour-bay was clear as glass,
+So smoothly it was strewn!
+And on the bay the moonlight lay,
+And the shadow of the Moon.
+
+The rock shone bright, the kirk no less,
+That stands above the rock:
+The moonlight steeped in silentness
+The steady weathercock.
+
+And the bay was white with silent light,
+Till rising from the same,
+Full many shapes, that shadows were,
+In crimson colours came.
+
+A little distance from the prow
+Those crimson shadows were:
+I turned my eyes upon the deck—
+Oh, Christ! what saw I there!
+
+Each corse lay flat, lifeless and flat,
+And, by the holy rood!
+A man all light, a seraph-man,
+On every corse there stood.
+
+This seraph-band, each waved his hand:
+It was a heavenly sight!
+They stood as signals to the land,
+Each one a lovely light;
+
+This seraph-band, each waved his hand,
+No voice did they impart—
+No voice; but oh! the silence sank
+Like music on my heart.
+
+But soon I heard the dash of oars,
+I heard the Pilot's cheer;
+My head was turned perforce away
+And I saw a boat appear.
+
+The Pilot and the Pilot's boy,
+I heard them coming fast:
+Dear Lord in Heaven! it was a joy
+The dead men could not blast.
+
+I saw a third—I heard his voice:
+It is the Hermit good!
+He singeth loud his godly hymns
+That he makes in the wood.
+He'll shrieve my soul, he'll wash away
+The Albatross's blood.
+
+PART VII
+This Hermit good lives in that wood
+Which slopes down to the sea.
+How loudly his sweet voice he rears!
+He loves to talk with marineres
+That come from a far countree.
+
+He kneels at morn, and noon, and eve—
+He hath a cushion plump:
+It is the moss that wholly hides
+The rotted old oak-stump.
+
+The skiff-boat neared: I heard them talk,
+'Why, this is strange, I trow!
+Where are those lights so many and fair,
+That signal made but now?'
+
+'Strange, by my faith!' the Hermit said—
+'And they answered not our cheer!
+The planks looked warped! and see those sails,
+How thin they are and sere!
+I never saw aught like to them,
+Unless perchance it were
+
+Brown skeletons of leaves that lag
+My forest-brook along;
+When the ivy-tod is heavy with snow,
+And the owlet whoops to the wolf below,
+That eats the she-wolf's young.'
+
+'Dear Lord! it hath a fiendish look—
+(The Pilot made reply)
+I am a-feared'—'Push on, push on!'
+Said the Hermit cheerily.
+
+The boat came closer to the ship,
+But I nor spake nor stirred;
+The boat came close beneath the ship,
+And straight a sound was heard.
+
+Under the water it rumbled on,
+Still louder and more dread:
+It reached the ship, it split the bay;
+The ship went down like lead.
+
+Stunned by that loud and dreadful sound,
+Which sky and ocean smote,
+Like one that hath been seven days drowned
+My body lay afloat;
+But swift as dreams, myself I found
+Within the Pilot's boat.
+
+Upon the whirl, where sank the ship,
+The boat spun round and round;
+And all was still, save that the hill
+Was telling of the sound.
+
+I moved my lips—the Pilot shrieked
+And fell down in a fit;
+The holy Hermit raised his eyes,
+And prayed where he did sit.
+
+I took the oars: the Pilot's boy,
+Who now doth crazy go,
+Laughed loud and long, and all the while
+His eyes went to and fro.
+'Ha! ha!' quoth he, 'full plain I see,
+The Devil knows how to row.'
+
+And now, all in my own countree,
+I stood on the firm land!
+The Hermit stepped forth from the boat,
+And scarcely he could stand.
+
+'O shrieve me, shrieve me, holy man!'
+The Hermit crossed his brow.
+'Say quick,' quoth he, 'I bid thee say—
+What manner of man art thou?'
+
+Forthwith this frame of mine was wrenched
+With a woful agony,
+Which forced me to begin my tale;
+And then it left me free.
+
+
+Since then, at an uncertain hour,
+That agony returns:
+And till my ghastly tale is told,
+This heart within me burns.
+
+I pass, like night, from land to land;
+I have strange power of speech;
+That moment that his face I see,
+I know the man that must hear me:
+To him my tale I teach.
+
+What loud uproar bursts from that door!
+The wedding-guests are there:
+But in the garden-bower the bride
+And bride-maids singing are:
+And hark the little vesper bell,
+Which biddeth me to prayer!
+
+O Wedding-Guest! this soul hath been
+Alone on a wide wide sea:
+So lonely 'twas, that God himself
+Scarce seemèd there to be.
+
+O sweeter than the marriage-feast,
+'Tis sweeter far to me,
+To walk together to the kirk
+With a goodly company!—
+
+To walk together to the kirk,
+And all together pray,
+While each to his great Father bends,
+Old men, and babes, and loving friends
+And youths and maidens gay!
+
+Farewell, farewell! but this I tell
+To thee, thou Wedding-Guest!
+He prayeth well, who loveth well
+Both man and bird and beast.
+
+He prayeth best, who loveth best
+All things both great and small;
+For the dear God who loveth us,
+He made and loveth all.
+
+The Mariner, whose eye is bright,
+Whose beard with age is hoar,
+Is gone: and now the Wedding-Guest
+Turned from the bridegroom's door.
+
+He went like one that hath been stunned,
+And is of sense forlorn:
+A sadder and a wiser man,
+He rose the morrow morn.

ADDED   src/0dev.org/commands/plaindiff/rime2.txt
Index: src/0dev.org/commands/plaindiff/rime2.txt
==================================================================
--- src/0dev.org/commands/plaindiff/rime2.txt
+++ src/0dev.org/commands/plaindiff/rime2.txt
@@ -0,0 +1,781 @@
+It is an ancient Mariner,
+And he stoppeth one of three.
+'By thy long grey beard and glittering eye,
+Now wherefore stopp'st thou me?
+
+The Bridegroom's doors are opened wide,
+And I am next of kin;
+The guests are met, the feast is set:
+May'st hear the merry din.'
+
+The Bridegroom's doors are opened wide,
+And I am next of kin;
+The guests are met, the feast is set:
+May'st hear the merry din.'
+
+
+He holds him with his skinny hand,
+'There was a ship,' quoth he.
+'Hold off! unhand me, grey-beard loon!'
+Eftsoons his hand dropt he.
+
+He holds him with his glittering eye—
+The Wedding-Guest stood still,
+And listens like a three years' child:
+The Mariner hath his will.
+
+The Wedding-Guest sat on a stone:
+He cannot choose but hear;
+And thus spake on that ancient man,
+The bright-eyed Mariner.
+
+'The ship was cheered, the harbour cleared,
+Merrily did we drop
+Below the kirk, below the hill,
+Below the lighthouse top.
+
+The Sun came up upon the left,
+Out of the sea came he!
+And he shone bright, and on the right
+Went down into the sea.
+
+Higher and higher every day,
+Till over the mast at noon—'
+The Wedding-Guest here beat his breast,
+For he heard the loud bassoon.
+
+The bride hath paced into the hall,
+Red as a rose is she;
+Nodding their heads before her goes
+The merry minstrelsy.
+
+The Wedding-Guest he beat his breast,
+Yet he cannot choose but hear;
+And thus spake on that ancient man,
+The bright-eyed Mariner.
+
+And now the STORM-BLAST came, and he
+Was tyrannous and strong:
+He struck with his o'ertaking wings,
+And chased us south along.
+
+With sloping masts and dipping prow,
+As who pursued with yell and blow
+Still treads the shadow of his foe,
+And forward bends his head,
+The ship drove fast, loud roared the blast,
+And southward aye we fled.
+
+And now there came both mist and snow,
+And it grew wondrous cold:
+And ice, mast-high, came floating by,
+As green as emerald.
+
+And through the drifts the snowy clifts
+Did send a dismal sheen:
+Nor shapes of men nor beasts we ken—
+The ice was all between.
+
+The ice was here, the ice was there,
+The ice was all around:
+It cracked and growled, and roared and howled,
+Like noises in a swound!
+
+At length did cross an Albatross,
+Thorough the fog it came;
+As if it had been a Christian soul,
+We hailed it in God's name.
+
+It ate the food it ne'er had eat,
+And round and round it flew.
+The ice did split with a thunder-fit;
+The helmsman steered us through!
+
+And a good south wind sprung up behind;
+The Albatross did follow,
+And every day, for food or play,
+Came to the mariner's hollo!
+
+In mist or cloud, on mast or shroud,
+It perched for vespers nine;
+Whiles all the night, through fog-smoke white,
+Glimmered the white Moon-shine.'
+
+'God save thee, ancient Mariner!
+From the fiends, that plague thee thus!—
+Why look'st thou so?'—With my cross-bow
+I shot the ALBATROSS.
+
+PART II
+The Sun now rose upon the right:
+Out of the sea came he,
+Still hid in mist, and on the left
+Went down into the sea.
+
+And the good south wind still blew behind,
+But no sweet bird did follow,
+Nor any day for food or play
+Came to the mariner's hollo!
+
+And I had done a hellish thing,
+And it would work 'em woe:
+For all averred, I had killed the bird
+That made the breeze to blow.
+Ah wretch! said they, the bird to slay,
+That made the breeze to blow!
+
+Nor dim nor red, like God's own head,
+The glorious Sun uprist:
+Then all averred, I had killed the bird
+That brought the fog and mist.
+'Twas right, said they, such birds to slay,
+That bring the fog and mist.
+
+The fair breeze blew, the white foam flew,
+The furrow followed free;
+We were the first that ever burst
+Into that silent sea.
+
+Down dropt the breeze, the sails dropt down,
+'Twas sad as sad could be;
+And we did speak only to break
+The silence of the sea!
+
+All in a hot and copper sky,
+The bloody Sun, at noon,
+Right up above the mast did stand,
+No bigger than the Moon.
+
+Day after day, day after day,
+We stuck, nor breath nor motion;
+As idle as a painted ship
+Upon a painted ocean.
+
+Water, water, every where,
+And all the boards did shrink;
+Water, water, every where,
+Nor any drop to drink.
+
+The very deep did rot: O Christ!
+That ever this should be!
+Yea, slimy things did crawl with legs
+Upon the slimy sea.
+
+About, about, in reel and rout
+The death-fires danced at night;
+The water, like a witch's oils,
+Burnt green, and blue and white.
+
+And some in dreams assurèd were
+Of the Spirit that plagued us so;
+Nine fathom deep he had followed us
+From the land of mist and snow.
+
+And every tongue, through utter drought,
+Was withered at the root;
+We could not speak, no more than if
+We had been choked with soot.
+
+Ah! well a-day! what evil looks
+Had I from old and young!
+Instead of the cross, the Albatross
+About my neck was hung.
+
+PART III
+There passed a weary time. Each throat
+Was parched, and glazed each eye.
+A weary time! a weary time!
+How glazed each weary eye,
+
+When looking westward, I beheld
+A something in the sky.
+
+At first it seemed a little speck,
+And then it seemed a mist;
+It moved and moved, and took at last
+A certain shape, I wist.
+
+A speck, a mist, a shape, I wist!
+And still it neared and neared:
+As if it dodged a water-sprite,
+It plunged and tacked and veered.
+
+With throats unslaked, with black lips baked,
+We could nor laugh nor wail;
+Through utter drought all dumb we stood!
+I bit my arm, I sucked the blood,
+And cried, A sail! a sail!
+
+With throats unslaked, with black lips baked,
+Agape they heard me call:
+Gramercy! they for joy did grin,
+And all at once their breath drew in.
+As they were drinking all.
+
+See! see! (I cried) she tacks no more!
+Hither to work us weal;
+Without a breeze, without a tide,
+She steadies with upright keel!
+
+The western wave was all a-flame.
+The day was well nigh done!
+Almost upon the western wave
+Rested the broad bright Sun;
+When that strange shape drove suddenly
+Betwixt us and the Sun.
+
+And straight the Sun was flecked with bars,
+(Heaven's Mother send us grace!)
+As if through a dungeon-grate he peered
+With broad and burning face.
+
+Alas! (thought I, and my heart beat loud)
+How fast she nears and nears!
+Are those her sails that glance in the Sun,
+Like restless gossameres?
+
+Are those her ribs through which the Sun
+Did peer, as through a grate?
+And is that Woman all her crew?
+Is that a DEATH? and are there two?
+Is DEATH that woman's mate?
+
+Her lips were red, her looks were free,
+Her locks were yellow as gold:
+Her skin was as white as leprosy,
+The Night-mare LIFE-IN-DEATH was she,
+Who thicks man's blood with cold.
+
+The naked hulk alongside came,
+And the twain were casting dice;
+'The game is done! I've won! I've won!'
+Quoth she, and whistles thrice.
+
+The Sun's rim dips; the stars rush out;
+At one stride comes the dark;
+With far-heard whisper, o'er the sea,
+Off shot the spectre-bark.
+
+One after one, by the star-dogged Moon,
+Too quick for groan or sigh,
+Each turned his face with a ghastly pang,
+And cursed me with his eye.
+
+We listened and looked sideways up!
+Fear at my heart, as at a cup,
+My life-blood seemed to sip!
+The stars were dim, and thick the night,
+The steersman's face by his lamp gleamed white;
+From the sails the dew did drip—
+Till clomb above the eastern bar
+The hornèd Moon, with one bright star
+Within the nether tip.
+
+Four times fifty living men,
+(And I heard nor sigh nor groan)
+With heavy thump, a lifeless lump,
+They dropped down one by one.
+
+The souls did from their bodies fly,—
+They fled to bliss or woe!
+And every soul, it passed me by,
+Like the whizz of my cross-bow!
+
+PART IV
+'I fear thee, ancient Mariner!
+I fear thy skinny hand!
+And thou art long, and lank, and brown,
+As is the ribbed sea-sand.
+
+I fear thee and thy glittering eye,
+And thy skinny hand, so brown.'—
+Fear not, fear not, thou Wedding-Guest!
+This body dropt not down.
+
+Alone, alone, all, all alone,
+Alone on a wide wide sea!
+And never a saint took pity on
+My soul in agony.
+
+The many men, so beautiful!
+And they all dead did lie:
+And a thousand thousand slimy things
+Lived on; and so did I.
+
+I looked upon the rotting sea,
+And drew my eyes away;
+I looked upon the rotting deck,
+And there the dead men lay.
+
+I looked to heaven, and tried to pray;
+But or ever a prayer had gusht,
+A wicked whisper came, and made
+My heart as dry as dust.
+
+I closed my lids, and kept them close,
+And the balls like pulses beat;
+For the sky and the sea, and the sea and the sky
+Lay dead like a load on my weary eye,
+And the dead were at my feet.
+
+The cold sweat melted from their limbs,
+Nor rot nor reek did they:
+The look with which they looked on me
+Had never passed away.
+
+An orphan's curse would drag to hell
+A spirit from on high;
+But oh! more horrible than that
+Is the curse in a dead man's eye!
+Seven days, seven nights, I saw that curse,
+And yet I could not die.
+
+The moving Moon went up the sky,
+And no where did abide:
+Softly she was going up,
+And a star or two beside—
+
+Her beams bemocked the sultry main,
+Like April hoar-frost spread;
+But where the ship's huge shadow lay,
+The charmèd water burnt alway
+A still and awful red.
+
+Beyond the shadow of the ship,
+I watched the water-snakes:
+They moved in tracks of shining white,
+And when they reared, the elfish light
+Fell off in hoary flakes.
+
+Within the shadow of the ship
+I watched their rich attire:
+Blue, glossy green, and velvet black,
+They coiled and swam; and every track
+Was a flash of golden fire.
+
+O happy living things! no tongue
+Their beauty might declare:
+A spring of love gushed from my heart,
+And I blessed them unaware:
+Sure my kind saint took pity on me,
+And I blessed them unaware.
+
+The self-same moment I could pray;
+And from my neck so free
+The Albatross fell off, and sank
+Like lead into the sea.
+
+PART V
+Oh sleep! it is a gentle thing,
+Beloved from pole to pole!
+To Mary Queen the praise be given!
+She sent the gentle sleep from Heaven,
+That slid into my soul.
+
+The silly buckets on the deck,
+That had so long remained,
+I dreamt that they were filled with dew;
+And when I awoke, it rained.
+
+My lips were wet, my throat was cold,
+My garments all were dank;
+Sure I had drunken in my dreams,
+And still my body drank.
+
+I moved, and could not feel my limbs:
+I was so light—almost
+I thought that I had died in sleep,
+And was a blessed ghost.
+
+And soon I heard a roaring wind:
+It did not come anear;
+But with its sound it shook the sails,
+That were so thin and sere.
+
+The upper air burst into life!
+And a hundred fire-flags sheen,
+To and fro they were hurried about!
+And to and fro, and in and out,
+The wan stars danced between.
+
+And the coming wind did roar more loud,
+And the sails did sigh like sedge,
+And the rain poured down from one black cloud;
+The Moon was at its edge.
+
+The thick black cloud was cleft, and still
+The Moon was at its side:
+Like waters shot from some high crag,
+The lightning fell with never a jag,
+A river steep and wide.
+
+The loud wind never reached the ship,
+Yet now the ship moved on!
+Beneath the lightning and the Moon
+The dead men gave a groan.
+
+They groaned, they stirred, they all uprose,
+Nor spake, nor moved their eyes;
+It had been strange, even in a dream,
+To have seen those dead men rise.
+
+The helmsman steered, the ship moved on;
+Yet never a breeze up-blew;
+The mariners all 'gan work the ropes,
+Where they were wont to do;
+They raised their limbs like lifeless tools—
+We were a ghastly crew.
+
+The body of my brother's son
+Stood by me, knee to knee:
+The body and I pulled at one rope,
+But he said nought to me.
+
+'I fear thee, ancient Mariner!'
+Be calm, thou Wedding-Guest!
+'Twas not those souls that fled in pain,
+Which to their corses came again,
+But a troop of spirits blest:
+
+For when it dawned—they dropped their arms,
+And clustered round the mast;
+Sweet sounds rose slowly through their mouths,
+And from their bodies passed.
+
+Around, around, flew each sweet sound,
+Then darted to the Sun;
+Slowly the sounds came back again,
+Now mixed, now one by one.
+
+Sometimes a-dropping from the sky
+I heard the sky-lark sing;
+Sometimes all little birds that are,
+How they seemed to fill the sea and air
+With their sweet jargoning!
+
+And now 'twas like all instruments,
+Now like a lonely flute;
+And now it is an angel's song,
+That makes the heavens be mute.
+
+It ceased; yet still the sails made on
+A pleasant noise till noon,
+A noise like of a hidden brook
+In the leafy month of June,
+That to the sleeping woods all night
+Singeth a quiet tune.
+
+Till noon we quietly sailed on,
+Yet never a breeze did breathe:
+Slowly and smoothly went the ship,
+Moved onward from beneath.
+
+Under the keel nine fathom deep,
+From the land of mist and snow,
+The spirit slid: and it was he
+That made the ship to go.
+The sails at noon left off their tune,
+And the ship stood still also.
+
+The Sun, right up above the mast,
+Had fixed her to the ocean:
+But in a minute she 'gan stir,
+With a short uneasy motion—
+Backwards and forwards half her length
+With a short uneasy motion.
+
+Then like a pawing horse let go,
+She made a sudden bound:
+It flung the blood into my head,
+And I fell down in a swound.
+
+How long in that same fit I lay,
+I have not to declare;
+But ere my living life returned,
+I heard and in my soul discerned
+Two voices in the air.
+
+'Is it he?' quoth one, 'Is this the man?
+By him who died on cross,
+With his cruel bow he laid full low
+The harmless Albatross.
+
+The spirit who bideth by himself
+In the land of mist and snow,
+He loved the bird that loved the man
+Who shot him with his bow.'
+
+The other was a softer voice,
+As soft as honey-dew:
+Quoth he, 'The man hath penance done,
+And penance more will do.'
+
+PART VI
+
+First Voice
+'But tell me, tell me! speak again,
+Thy soft response renewing—
+What makes that ship drive on so fast?
+What is the ocean doing?'
+
+Second Voice
+Still as a slave before his lord,
+The ocean hath no blast;
+His great bright eye most silently
+Up to the Moon is cast—
+
+If he may know which way to go;
+For she guides him smooth or grim.
+See, brother, see! how graciously
+She looketh down on him.'
+
+First Voice
+'But why drives on that ship so fast,
+Without or wave or wind?'
+
+Second Voice
+'The air is cut away before,
+And closes from behind.
+
+Fly, brother, fly! more high, more high!
+Or we shall be belated:
+For slow and slow that ship will go,
+When the Mariner's trance is abated.'
+
+I woke, and we were sailing on
+As in a gentle weather:
+'Twas night, calm night, the moon was high;
+The dead men stood together.
+
+All stood together on the deck,
+For a charnel-dungeon fitter:
+All fixed on me their stony eyes,
+That in the Moon did glitter.
+
+The pang, the curse, with which they died,
+Had never passed away:
+I could not draw my eyes from theirs,
+Nor turn them up to pray.
+
+And now this spell was snapt: once more
+I viewed the ocean green,
+And looked far forth, yet little saw
+Of what had else been seen—
+
+Like one, that on a lonesome road
+Doth walk in fear and dread,
+And having once turned round walks on,
+And turns no more his head;
+Because he knows, a frightful fiend
+Doth close behind him tread.
+
+But soon there breathed a wind on me,
+Nor sound nor motion made:
+Its path was not upon the sea,
+In ripple or in shade.
+
+It raised my hair, it fanned my cheek
+Like a meadow-gale of spring—
+It mingled strangely with my fears,
+Yet it felt like a welcoming.
+
+Swiftly, swiftly flew the ship,
+Yet she sailed softly too:
+Sweetly, sweetly blew the breeze—
+On me alone it blew.
+
+Oh! dream of joy! is this indeed
+The light-house top I see?
+Is this the hill? is this the kirk?
+Is this mine own countree?
+
+We drifted o'er the harbour-bar,
+And I with sobs did pray—
+O let me be awake, my God!
+Or let me sleep alway.
+
+The harbour-bay was clear as glass,
+So smoothly it was strewn!
+And on the bay the moonlight lay,
+And the shadow of the Moon.
+
+The rock shone bright, the kirk no less,
+That stands above the rock:
+The moonlight steeped in silentness
+The steady weathercock.
+
+And the bay was white with silent light,
+Till rising from the same,
+Full many shapes, that shadows were,
+In crimson colours came.
+
+A little distance from the prow
+Those crimson shadows were:
+I turned my eyes upon the deck—
+Oh, Christ! what saw I there!
+
+Each corse lay flat, lifeless and flat,
+And, by the holy rood!
+A man all light, a seraph-man,
+On every corse there stood.
+
+This seraph-band, each waved his hand:
+It was a heavenly sight!
+They stood as signals to the land,
+Each one a lovely light;
+
+This seraph-band, each waved his hand,
+No voice did they impart—
+No voice; but oh! the silence sank
+Like music on my heart.
+
+But soon I heard the dash of oars,
+I heard the Pilot's cheer;
+My head was turned perforce away
+And I saw a boat appear.
+
+The Pilot and the Pilot's boy,
+I heard them coming fast:
+Dear Lord in Heaven! it was a joy
+The dead men could not blast.
+
+I saw a third—I heard his voice:
+It is the Hermit good!
+He singeth loud his godly hymns
+That he makes in the wood.
+He'll shrieve my soul, he'll wash away
+The Albatross's blood.
+
+PART VII
+This Hermit good lives in that wood
+Which slopes down to the sea.
+How loudly his sweet voice he rears!
+He loves to talk with marineres
+That come from a far countree.
+
+He kneels at morn, and noon, and eve—
+He hath a cushion plump:
+It is the moss that wholly hides
+The rotted old oak-stump.
+
+The skiff-boat neared: I heard them talk,
+'Why, this is strange, I trow!
+Where are those lights so many and fair,
+That signal made but now?'
+
+'Strange, by my faith!' the Hermit said—
+'And they answered not our cheer!
+The planks looked warped! and see those sails,
+How thin they are and sere!
+I never saw aught like to them,
+Unless perchance it were
+
+Brown skeletons of leaves that lag
+My forest-brook along;
+When the ivy-tod is heavy with snow,
+And the owlet whoops to the wolf below,
+That eats the she-wolf's young.'
+
+'Dear Lord! it hath a fiendish look—
+(The Pilot made reply)
+I am a-feared'—'Push on, push on!'
+Said the Hermit cheerily.
+
+The boat came closer to the ship,
+But I nor spake nor stirred;
+The boat came close beneath the ship,
+And straight a sound was heard.
+
+Under the water it rumbled on,
+Still louder and more dread:
+It reached the ship, it split the bay;
+The ship went down like lead.
+
+Stunned by that loud and dreadful sound,
+Which sky and ocean smote,
+Like one that hath been seven days drowned
+My body lay afloat;
+But swift as dreams, myself I found
+Within the Pilot's boat.
+
+Upon the whirl, where sank the ship,
+The boat spun round and round;
+And all was still, save that the hill
+Was telling of the sound.
+
+I moved my lips—the Pilot shrieked
+And fell down in a fit;
+The holy Hermit raised his eyes,
+And prayed where he did sit.
+
+I took the oars: the Pilot's boy,
+Who now doth crazy go,
+Laughed loud and long, and all the while
+His eyes went to and fro.
+'Ha! ha!' quoth he, 'full plain I see,
+The Devil knows how to row.'
+
+And now, all in my own countree,
+I stood on the firm land!
+The Hermit stepped forth from the boat,
+And scarcely he could stand.
+
+'O shrieve me, shrieve me, holy man!'
+The Hermit crossed his brow.
+'Say quick,' quoth he, 'I bid thee say—
+What manner of man art thou?'
+
+Forthwith this frame of mine was wrenched
+With a woful agony,
+Which forced me to begin my tale;
+And then it left me free.
+
+
+Since then, at an uncertain hour,
+That agony returns:
+And till my ghastly tale is told,
+This heart within me burns.
+
+I pass, like night, from land to land;
+I have strange power of speech;
+That moment that his face I see,
+I know the man that must hear me:
+To him my tale I teach.
+
+What loud uproar bursts from that door!
+The wedding-guests are there:
+But in the garden-bower the bride
+And bride-maids singing are:
+And hark the little vesper bell,
+Which biddeth me to prayer!
+
+O Wedding-Guest! this soul hath been
+Alone on a wide wide sea:
+So lonely 'twas, that God himself
+Scarce seemèd there to be.
+
+O sweeter than the marriage-feast,
+'Tis sweeter far to me,
+To walk together to the kirk
+With a goodly company!—
+
+To walk together to the kirk,
+And all together pray,
+While each to his great Father bends,
+Old men, and babes, and loving friends
+And youths and maidens gay!
+
+Farewell, farewell! but this I tell
+To thee, thou Wedding-Guest!
+He prayeth well, who loveth well
+Both man and bird and beast.
+
+He prayeth best, who loveth best
+All things both great and small;
+For the dear God who loveth us,
+He made and loveth all.
+
+He went like one that hath been stunned,
+And is of sense forlorn:
+A sadder and a wiser man,
+He rose the morrow morn.

ADDED   src/0dev.org/diff/diff.go
Index: src/0dev.org/diff/diff.go
==================================================================
--- src/0dev.org/diff/diff.go
+++ src/0dev.org/diff/diff.go
@@ -0,0 +1,130 @@
+// Package diff provides a diff implementation
+// for finite, indexable sequences with comparable elements
+package diff
+
+import (
+	bits "0dev.org/bits"
+)
+
+// Interface abstracts the required knowledge to perform a diff
+// on any two comparable, fixed-length sequences
+type Interface interface {
+	// The sequences' lengths
+	Len() (int, int)
+	// True when the sequences' elements at those indices are equal
+	Equal(int, int) bool
+}
+
+// A Mark struct marks a length in sequence starting with an offset
+type Mark struct {
+	From   int
+	Length int
+}
+
+// A Delta struct is the result of a Diff operation
+type Delta struct {
+	Added   []Mark
+	Removed []Mark
+}
+
+// Diffs the provided data and returns e Delta struct
+// with added entries' indices in the second sequence and removed from the first
+func Diff(data Interface) Delta {
+	var len1, len2 = data.Len()
+	var mat matrix = matrix{v: bits.New(uint(len1 * len2)), lenX: len1, lenY: len2}
+
+	for i := 0; i < len1; i++ {
+		for j := 0; j < len2; j++ {
+			mat.v.Poke(mat.at(i, j), data.Equal(i, j))
+		}
+	}
+
+	return recursiveDiff(box{0, 0, len1, len2}, mat)
+}
+
+type match struct {
+	x, y   int
+	length int
+}
+
+type box struct {
+	x, y       int
+	lenX, lenY int
+}
+
+// A helper structure that stores absolute dimension along a linear bit vector
+// so that it can always properly translate (x, y) -> z on the vector
+type matrix struct {
+	v          bits.Vector
+	lenX, lenY int
+}
+
+// Translates (x, y) to an absolute position on the bit vector
+func (m *matrix) at(x, y int) uint {
+	return uint(y + (x * m.lenY))
+}
+
+func recursiveDiff(bounds box, mat matrix) Delta {
+	var m match = largest(bounds, mat)
+
+	if m.length == 0 { // Recursion terminates
+		var immediate Delta
+		if bounds.lenY-bounds.y > 0 {
+			immediate.Added = []Mark{Mark{bounds.y, bounds.lenY}}
+		}
+		if bounds.lenX-bounds.x > 0 {
+			immediate.Removed = []Mark{Mark{bounds.x, bounds.lenX}}
+		}
+		return immediate
+	}
+
+	var left Delta = recursiveDiff(box{bounds.x, bounds.y, m.x, m.y}, mat)
+	var right Delta = recursiveDiff(box{m.x + m.length, m.y + m.length, bounds.lenX, bounds.lenY}, mat)
+
+	var result Delta
+
+	result.Added = append(left.Added, right.Added...)
+	result.Removed = append(left.Removed, right.Removed...)
+
+	return result
+}
+
+// Finds the largest common substring by looking at the provided match matrix
+// starting from (bounds.x, bounds.y) with lengths bounds.lenX, bounds.lenY
+func largest(bounds box, mat matrix) (result match) {
+	for i := bounds.x; i < bounds.lenX; i++ {
+		var m match = search(i, bounds.y, bounds.lenX, bounds.lenY, mat)
+		if m.length > result.length {
+			result = m
+		}
+	}
+	for j := bounds.y + 1; j < bounds.lenY; j++ {
+		var m match = search(bounds.x, j, bounds.lenX, bounds.lenY, mat)
+		if m.length > result.length {
+			result = m
+		}
+	}
+	return
+}
+
+// Searches the main diagonal for the longest sequential match line
+func search(x, y, lenX, lenY int, mat matrix) (result match) {
+	var inMatch bool
+	var m match
+	for step := 0; step+x < lenX && step+y < lenY; step++ {
+		if mat.v.Peek(mat.at(step+x, step+y)) {
+			if !inMatch { // Create a new current record if there is none ...
+				inMatch, m.x, m.y, m.length = true, step+x, step+y, 1
+			} else { // ... otherwise just increment the existing
+				m.length++
+			}
+
+			if m.length > result.length {
+				result = m // Store it if it is longer ...
+			}
+		} else { // End of current of match
+			inMatch = false // ... and reset the current one
+		}
+	}
+	return
+}

ADDED   src/0dev.org/diff/diff_test.go
Index: src/0dev.org/diff/diff_test.go
==================================================================
--- src/0dev.org/diff/diff_test.go
+++ src/0dev.org/diff/diff_test.go
@@ -0,0 +1,72 @@
+package diff
+
+import (
+	bits "0dev.org/bits"
+	"fmt"
+	"testing"
+)
+
+type diffSlice struct {
+	first  []rune
+	second []rune
+}
+
+func (d diffSlice) Len() (int, int) {
+	return len(d.first), len(d.second)
+}
+
+func (d diffSlice) Equal(i, j int) bool {
+	return d.first[i] == d.second[j]
+}
+
+func TestLCS(t *testing.T) {
+	fmt.Println("")
+
+	data := diffSlice{
+		[]rune("abcdefgh"),
+		[]rune("abbcedfh"),
+	}
+
+	fmt.Println(Diff(data))
+
+	// first, second, total := LCS(data)
+	// fmt.Println(first, second, total)
+}
+
+func TestWTF(t *testing.T) {
+	data := diffSlice{
+		[]rune("abcdefgh"),
+		[]rune("abbcedfh"),
+	}
+
+	var len1, len2 int = data.Len()
+	var mat matrix = matrix{v: bits.NewBool(uint(len1 * len2)), lenX: len1, lenY: len2}
+
+	for i := 0; i < len1; i++ {
+		for j := 0; j < len2; j++ {
+			mat.v.Poke(mat.at(i, j), data.Equal(i, j))
+		}
+	}
+
+	debugPrint(box{5, 5, 6, 6}, mat)
+	debugPrint(box{5, 5, 7, 7}, mat)
+	debugPrint(box{5, 5, 8, 8}, mat)
+}
+
+func debugPrint(bounds box, mat matrix) {
+	// Debug print
+	fmt.Printf("-%d-%d--%d-%d--\n", bounds.x, bounds.y, bounds.lenX, bounds.lenY)
+	for i := bounds.x; i < bounds.lenX; i++ {
+		fmt.Print("| ")
+		for j := bounds.y; j < bounds.lenY; j++ {
+			//if vector.Peek(uint(j + (i * bounds.lenY))) {
+			if mat.v.Peek(mat.at(i, j)) {
+				fmt.Print("\\")
+			} else {
+				fmt.Print(".")
+			}
+		}
+		fmt.Println(" |")
+	}
+	fmt.Println("------------")
+}

ADDED   src/0dev.org/math/math.go
Index: src/0dev.org/math/math.go
==================================================================
--- src/0dev.org/math/math.go
+++ src/0dev.org/math/math.go
@@ -0,0 +1,16 @@
+// Helper functions that really belong in the SDK or in a generic library...
+package math
+
+func MinInt(i1, i2 int) int {
+	if i1 <= i2 {
+		return i1
+	}
+	return i2
+}
+
+func MaxInt(i1, i2 int) int {
+	if i1 >= i2 {
+		return i1
+	}
+	return i2
+}