From 8cbc141a94ad94d9d85044362644e93cf1c4f6a7 Mon Sep 17 00:00:00 2001
From: Nathan Daly <nhdaly@gmail.com>
Date: Sat, 26 Jan 2019 19:21:24 -0500
Subject: [PATCH] Add S35_Reformat by reusing S33_DISASSEMBLE and S34_ASSEMBLE

---
 src/CspExamples.jl  | 17 +++++++++++++++++
 test/CspExamples.jl |  9 ++++++++-
 2 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/src/CspExamples.jl b/src/CspExamples.jl
index 46b8c50..54ffae3 100644
--- a/src/CspExamples.jl
+++ b/src/CspExamples.jl
@@ -127,4 +127,21 @@ function S34_ASSEMBLE(X::Channel{Char}, lineprinter::Channel{>:String}, lineleng
     end
 end
 
+"""
+    S35_Reformat
+
+3.5 Reformaeast "Problem: Read a sequence of cards of 80 characters each, and print
+the characters on a lineprinter at 125 characters per line. Every card
+should be followed by an extra space, and the last line should be
+completed with spaces if necessary."
+
+This one's fun! We can reuse the existing functions by creating an intermediate Channel and
+Task (equivalent to a Process in Hoare's paper) to act as the output and then input.
+"""
+function S35_Reformat(west::Channel{String}, east::Channel{>:String}, linelength=125)
+    S34_ASSEMBLE(Channel(ctype=Char) do ch
+                     S33_DISASSEMBLE(west, ch)
+                 end, east, linelength)
+end
+
 end
diff --git a/test/CspExamples.jl b/test/CspExamples.jl
index 87671f4..c69c0e4 100644
--- a/test/CspExamples.jl
+++ b/test/CspExamples.jl
@@ -40,7 +40,7 @@ end
 @testset "S32_SQUASH_EXT" begin
     # Test 1 * at end
     west = make_filled_channel("hello**world*")
-    east = Channel(ch->CspExamples.S32_SQUASH_EXT(west, ch), ctype=Char)
+    east = Channel(ch->CspExamples.S32_SQUASH_EXT(west, ch),ctype=Char)
     @test String(collect(east)) == "hello↑world*"
 
     # Test 3 *s at end
@@ -74,3 +74,10 @@ end
     expected = [String(expected[1+(i-1)*linelength:i*linelength]) for i in 1:2]
     @test collect(lineprinter) == expected
 end
+
+@testset "S35_Reformat" begin
+    reformatted = Channel() do ch
+        CspExamples.S35_Reformat(make_filled_channel(["hello", "world"]), ch, 4)
+    end
+    @test collect(reformatted) == ["hell", "o wo", "rld "]
+end