--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/code/tree.lm	Sat Jul 26 15:29:01 2014 -0700
@@ -0,0 +1,109 @@
+#{
+	makeTree:size <- :lst :size {
+		ret <- 0
+		sub <- 0
+		half <- size / 2
+		if: size = 2 {
+			ret <- #[(lst value) ((lst tail) value)]
+		} else: {
+			if: size = 1 {
+				ret <- lst
+			} else: {
+				sub <- split: lst at: half
+				ret <- #[
+					(makeTree: (sub value) size: half)
+					(makeTree: (sub tail) size: size-half)
+				]
+			}
+		}
+		ret
+	}
+	
+	makeTree <- :lst {
+		size <- lst length
+		#[size (makeTree: lst size: size)]
+	}
+	
+	get:fromTree:size <- :idx :tree :size {
+		ret <- 0
+		half <- size / 2
+		if: size <= 2 {
+			if: idx = 0 {
+				ret <- tree value
+			} else: {	
+				ret <- tree tail
+			}
+		} else: {
+			if: idx < half {
+				ret <- get: idx fromTree: (tree value) size: half
+			} else: {
+				ret <- get: idx-half fromTree: (tree tail) size: size-half
+			}
+		}
+		ret
+	}
+	
+	get:fromTree <- :idx :tree {
+		size <- tree value
+		get: idx fromTree: (tree tail) size: size
+	}
+	
+	treeMap:size <- :tree fun :size {
+		ret <- 0
+		half <- size / 2
+		if: size = 2 {
+			ret <- #[(fun: (tree value)) (fun: (tree tail))]
+		} else: {
+			if: size = 1 {
+				ret <- #[(fun: (tree value)) 0]
+			} else: {
+				ret <- #[
+					(treeMap: (tree value) fun size: half)
+					(treeMap: (tree tail) fun size: size-half)
+				]
+			}
+		}
+		ret
+	}
+	
+	treeMap <- :tree fun {	
+		#[(tree value) (treeMap: (tree tail) fun size: (tree value))]
+	}
+	
+	tree:size:update:with <- :tree :size :idx :fun {
+		ret <- 0
+		half <- size / 2
+		if: size = 2 {
+			if: idx = 0 {
+				ret <- #[(fun: (tree value)) (tree tail)]
+			} else: {
+				ret <- #[(tree value) (fun: (tree tail))]
+			}
+		} else: {
+			if: size = 1 {
+				ret <- #[(fun: (tree value)) 0]
+			} else: {
+				if: (idx < half) {
+					ret <- #[
+						(tree: (tree value) size: half update: idx with: fun)
+						(tree tail)
+					]
+				} else: {
+					ret <- #[
+						(tree value)
+						(tree: (tree tail) size: size-half update: idx-half with: fun)
+					]
+				}
+			}
+		}
+		ret
+	}
+	
+	tree:update:with <- :tree :idx :fun {
+		#[(tree value) (tree: (tree tail) size: (tree value) update: idx with: fun)]
+	}
+	
+	tree:set:to <- :tree :idx :val {
+		tree: tree update: idx with: :el { val }
+	}
+}
\ No newline at end of file