remove make_pair

There are better alternatives with C++11.

Signed-off-by: Rosen Penev <rosenp@gmail.com>

src/ast.cpp

@@ -232,33 +232,33 @@ static std::pair<source_range_t, const wchar_t *> find_block_open_keyword(const
                 break;
             case type_t::for_header: {
                 const auto *h = cursor->as<for_header_t>();
-                return std::make_pair(h->kw_for.range, L"for loop");
+                return {h->kw_for.range, L"for loop"};
             }
             case type_t::while_header: {
                 const auto *h = cursor->as<while_header_t>();
-                return std::make_pair(h->kw_while.range, L"while loop");
+                return {h->kw_while.range, L"while loop"};
             }
             case type_t::function_header: {
                 const auto *h = cursor->as<function_header_t>();
-                return std::make_pair(h->kw_function.range, L"function definition");
+                return {h->kw_function.range, L"function definition"};
             }
             case type_t::begin_header: {
                 const auto *h = cursor->as<begin_header_t>();
-                return std::make_pair(h->kw_begin.range, L"begin");
+                return {h->kw_begin.range, L"begin"};
             }
             case type_t::if_statement: {
                 const auto *h = cursor->as<if_statement_t>();
-                return std::make_pair(h->if_clause.kw_if.range, L"if statement");
+                return {h->if_clause.kw_if.range, L"if statement"};
             }
             case type_t::switch_statement: {
                 const auto *h = cursor->as<switch_statement_t>();
-                return std::make_pair(h->kw_switch.range, L"switch statement");
+                return {h->kw_switch.range, L"switch statement"};
             }
             default:
-                return std::make_pair(source_range_t{}, nullptr);
+                return {source_range_t{}, nullptr};
         }
     }
-    return std::make_pair(source_range_t{}, nullptr);
+    return {source_range_t{}, nullptr};
 }
 
 /// \return the decoration for this statement.

src/complete.cpp

@@ -701,7 +701,7 @@ void completer_t::complete_cmd_desc(const wcstring &str) {
         // And once again I make sure the first character is uppercased because I like it that
         // way, and I get to decide these things.
         val.at(0) = towupper(val.at(0));
-        lookup.insert(std::make_pair(std::move(key), std::move(val)));
+        lookup.emplace(std::move(key), std::move(val));
     }
 
     // Then do a lookup on every completion and if a match is found, change to the new

src/env.cpp

@@ -682,9 +682,9 @@ std::shared_ptr<owning_null_terminated_array_t> env_scoped_impl_t::create_export
         assert(var && "Variable should be present in uvars");
         // Note that std::map::insert does NOT overwrite a value already in the map,
         // which we depend on here.
-        // Note: Using std::move around make_pair prevents the compiler from implementing
+        // Note: Using std::move around emplace prevents the compiler from implementing
         // copy elision.
-        vals.insert(std::make_pair(key, std::move(*var)));
+        vals.emplace(key, std::move(*var));
     }
 
     // Dorky way to add our single exported computed variable.

src/highlight.cpp

@@ -387,7 +387,7 @@ rgb_color_t highlight_color_resolver_t::resolve_spec(const highlight_spec_t &hig
                                                      bool is_background,
                                                      const environment_t &vars) {
     auto &cache = is_background ? bg_cache_ : fg_cache_;
-    auto p = cache.insert(std::make_pair(highlight, rgb_color_t{}));
+    auto p = cache.emplace(highlight, rgb_color_t{});
     auto iter = p.first;
     bool did_insert = p.second;
     if (did_insert) {