ppgen: Use ostream_joiner

This allows for not printing a trailing space, which is better for
copy-pasting.

Bumps version to 1.2

meson.build

@@ -1,19 +1,23 @@
 project('ppgen', ['cpp'],
-	version: '1.1',
-	license: 'GPL3+',
+	    version: '1.2',
+	    license: 'GPL3+',
         default_options : ['cpp_std=c++14',
-			   'buildtype=release'])
+			               'buildtype=release'])
+
+if not meson.get_compiler('cpp').has_header_symbol('experimental/iterator', '__cpp_lib_experimental_ostream_joiner')
+  error('C++ ostream_joiner not available. Use release 1.1')
+endif
 
 pcg_cpp_sp = subproject('pcg-cpp')
 pcg_cpp_dep = pcg_cpp_sp.get_variable('pcg_cpp_dep')
 
-ppgen = executable('ppgen', join_paths('src', 'ppgen.cpp'),
-		   dependencies: pcg_cpp_dep,
-		   install: true)
+ppgen = executable('ppgen', 'src/ppgen.cpp',
+		           dependencies: pcg_cpp_dep,
+		           install: true)
 
-pingen = executable('pingen', join_paths('src', 'pingen.cpp'),
-		   dependencies: pcg_cpp_dep,
-		   install: true)
+pingen = executable('pingen', 'src/pingen.cpp',
+		            dependencies: pcg_cpp_dep,
+		            install: true)
 
-install_man(join_paths('man', 'ppgen.1'))
-install_man(join_paths('man', 'pingen.1'))
+install_man('man/ppgen.1')
+install_man('man/pingen.1')

src/ppgen.cpp

@@ -16,6 +16,7 @@
 #include <cmath>
 #include <iostream>
 #include <random>
+#include <experimental/iterator>
 #include "pcg_random.hpp"
 #include "diceware_wordlist.h"
 #include "eff_wordlist.h"
@@ -53,8 +54,9 @@ int main(int argc, char** arg_begin)
 
     std::cout << "Choose from one of these 10 passphrases:\n\n";
     for (int gen_num = 0; gen_num < 10; ++gen_num) {
+        auto out = std::experimental::make_ostream_joiner(std::cout, " ");
         for (long word = 0; word < num_words; ++word) {
-            std::cout << wordlist[dis(rng)] << " ";
+            out = wordlist[dis(rng)];
         }
         std::cout << std::endl;
     }