June 2018 Update

Task/Same-Fringe/Julia/same-fringe.julia

@@ -0,0 +1,50 @@
+using Lazy
+
+"""
+    Input a tree for display as a fringed structure.
+"""
+function fringe(tree)
+    fringey(node::Pair) = [fringey(i) for i in node]
+    fringey(leaf::Int) = leaf
+    fringey(tree)
+end
+
+
+"""
+    equalsfringe() uses a reduction to a lazy 1D list via
+    getleaflist() for its "equality" of fringes
+"""
+getleaflist(tree::Int) = [tree]
+getleaflist(tree::Pair) = vcat(getleaflist(seq(tree[1])), getleaflist(seq(tree[2])))
+getleaflist(tree::Lazy.LazyList) = vcat(getleaflist(tree[1]), getleaflist(tree[2]))
+getleaflist(tree::Void) = []
+equalsfringe(t1, t2) = (getleaflist(t1) == getleaflist(t2))
+
+
+a = 1 => 2 => 3 => 4 => 5 => 6 => 7 => 8
+b = 1 => (( 2 => 3 ) => (4 => (5 => ((6 => 7) => 8))))
+c = (((1 => 2) => 3) => 4) => 5 => 6 => 7 => 8
+
+x = 1 => 2 => 3 => 4 => 5 => 6 => 7 => 8 => 9
+y = 0 => 2 => 3 => 4 => 5 => 6 => 7 => 8
+z = 1 => 2 => (4 => 3) => 5 => 6 => 7 => 8
+
+prettyprint(s) = println(replace("$s", r"\{Any,1\}|Any|Array\{T,1\}\swhere\sT|Array|", ""))
+prettyprint(fringe(a))
+prettyprint(fringe(b))
+prettyprint(fringe(c))
+prettyprint(fringe(x))
+prettyprint(fringe(y))
+prettyprint(fringe(z))
+
+prettyprint(getleaflist(a))
+prettyprint(getleaflist(b))
+prettyprint(getleaflist(c))
+
+println(equalsfringe(a, a))
+println(equalsfringe(a, b))
+println(equalsfringe(a, c))
+println(equalsfringe(b, c))
+println(equalsfringe(a, x) == false)
+println(equalsfringe(a, y) == false)
+println(equalsfringe(a, z) == false)