Make options with implicit value use next token.

This commit reverts:

    - 88dea3c.
    "Stop options with implicit value from consuming separate tokens."

    - 0c01e9a.
    "Add testing for implicit_values and non-consuming of separate tokens."

These commits from 2014 made options with implicit_value set only
consult value in the same token. The problem is that now implicit_value,
a sematic properly, forces a particular syntax, which proved to be
confusing.

Author: vprus

include/boost/program_options/value_semantic.hpp

@@ -38,11 +38,6 @@ namespace boost { namespace program_options {
             should be present on the command line. */
         virtual unsigned max_tokens() const = 0;
 
-        /** Returns true if the option should only take adjacent token,
-            not one from further command-line arguments.
-        */
-        virtual bool adjacent_tokens_only() const = 0;
-
         /** Returns true if values from different sources should be composed.
             Otherwise, value from the first source is used and values from
             other sources are discarded.
@@ -53,7 +48,7 @@ namespace boost { namespace program_options {
 
         */
         virtual bool is_required() const = 0;
-
+        
         /** Parses a group of tokens that specify a value of option.
             Stores the result in 'value_store', using whatever representation
             is desired. May be be called several times if value of the same
@@ -139,7 +134,6 @@ namespace boost { namespace program_options {
 
         unsigned min_tokens() const;
         unsigned max_tokens() const;
-        bool adjacent_tokens_only() const { return false; }
 
         bool is_composing() const { return false; }
 
@@ -331,8 +325,6 @@ namespace boost { namespace program_options {
             }
         }
 
-        bool adjacent_tokens_only() const { return !m_implicit_value.empty(); }
-
         bool is_required() const { return m_required; }
 
         /** Creates an instance of the 'validator' class and calls

src/cmdline.cpp

@@ -313,9 +313,6 @@ namespace boost { namespace program_options { namespace detail {
             if (!xd)
                 continue;
 
-            if (xd->semantic()->adjacent_tokens_only())
-                continue;
-
             unsigned min_tokens = xd->semantic()->min_tokens();
             unsigned max_tokens = xd->semantic()->max_tokens();
             if (min_tokens < max_tokens && opt.value.size() < max_tokens)

test/cmdline_test.cpp

@@ -63,8 +63,7 @@ struct test_case {
    The "boost::program_options" in parameter type is needed because CW9 
    has std::detail and it causes an ambiguity.
 */
-void apply_syntax(options_description& desc,
-                  positional_options_description & m_positional,
+void apply_syntax(options_description& desc, 
                   const char* syntax)
 {
 
@@ -78,8 +77,8 @@ void apply_syntax(options_description& desc,
             v = value<string>();
             s.resize(s.size()-1);
         } else if (*(s.end()-1) == '?') {
-            v = value<string>()->implicit_value("bar");
-            m_positional.add("positional", -1);
+            //v = value<string>()->implicit();
+            v = value<string>();
             s.resize(s.size()-1);
         } else if (*(s.end()-1) == '*') {
             v = value<vector<string> >()->multitoken();
@@ -114,14 +113,12 @@ void test_cmdline(const char* syntax,
             }
         }
         options_description desc;
-        positional_options_description m_positional;
-        apply_syntax(desc, m_positional, syntax);
+        apply_syntax(desc, syntax);
 
         cmdline cmd(xinput);
         cmd.style(style);
         cmd.set_options_description(desc);
-        if(m_positional.max_total_count())
-            cmd.set_positional_options(m_positional);
+
 
         string result;
         int status = 0;
@@ -133,9 +130,7 @@ void test_cmdline(const char* syntax,
             {
                 option opt = options[j];
 
-                if (opt.position_key != -1
-                    && (m_positional.max_total_count() == 0 || (size_t)opt.position_key >= m_positional.max_total_count()
-                     || m_positional.name_for_position(opt.position_key) != "positional")) {
+                if (opt.position_key != -1) {
                     if (!result.empty())
                         result += " ";
                     result += opt.value[0];
@@ -233,7 +228,7 @@ void test_long_options()
         {"--giz", s_success, "Giz:"},
         {0, 0, 0}
     };
-    test_cmdline("foo bar= Giz", style, test_cases4);
+    test_cmdline("foo bar= baz? Giz", style, test_cases4);
 }
 
 void test_short_options()
@@ -353,15 +348,15 @@ void test_disguised_long()
         {"-bee=x -by", s_success, "bee:x bee:y"},
         {0, 0, 0}
     };
-    test_cmdline("foo,f goo,g= bee,b=", style, test_cases1);
+    test_cmdline("foo,f goo,g= bee,b?", style, test_cases1);
 
     style = cmdline::style_t(style | allow_slash_for_short);
     test_case test_cases2[] = {
         {"/foo -f", s_success, "foo: foo:"},
         {"/goo=x", s_success, "goo:x"},
         {0, 0, 0}
     };
-    test_cmdline("foo,f goo,g=", style, test_cases2);
+    test_cmdline("foo,f goo,g= bee,b?", style, test_cases2);
 }
 
 void test_guessing()
@@ -612,35 +607,6 @@ void test_unregistered()
     // It's not clear yet, so I'm leaving the decision till later.
 }
 
-void test_implicit_value()
-{
-    using namespace command_line_style;
-    cmdline::style_t style;
-
-    style = cmdline::style_t(
-        allow_long | long_allow_adjacent
-        );
-
-    test_case test_cases1[] = {
-        {"--foo bar", s_success, "foo: positional:bar"},
-        {"--foo=bar foobar", s_success, "foo:bar positional:foobar"},
-        {0, 0, 0}
-    };
-
-    test_cmdline("positional= foo?", style, test_cases1);
-
-    style = cmdline::style_t(
-        allow_short | allow_dash_for_short 
-        | short_allow_adjacent);
-
-    test_case test_cases2[] = {
-        {"-f bar", s_success, "-f: positional:bar"},
-        {"-fbar foobar", s_success, "-f:bar positional:foobar"},
-        {0, 0, 0}
-    };
-    test_cmdline("positional= ,f?", style, test_cases2);
-}
-
 int main(int /*ac*/, char** /*av*/)
 {
     test_long_options();
@@ -653,7 +619,6 @@ int main(int /*ac*/, char** /*av*/)
     test_additional_parser();
     test_style_parser();
     test_unregistered();
-    test_implicit_value();
 
     return 0;
 }