style(3p/nix): Remove 'using std::*' from types.hh

It is considered bad form to use things from includes in headers, as
these directives propagate to everywhere else and can make it
confusing.

types.hh (which is includes almost literally everywhere) had some of
these directives, which this commit removes.

third_party/nix/src/libexpr/parser.y

@@ -146,7 +146,7 @@ static void addFormal(const Pos & pos, Formals * formals, const Formal & formal)
 }
 
 
-static Expr * stripIndentation(const Pos & pos, SymbolTable & symbols, vector<Expr *> & es)
+static Expr * stripIndentation(const Pos & pos, SymbolTable & symbols, std::vector<Expr *> & es)
 {
     if (es.empty()) { return new ExprString(symbols.Create("")); }
 
@@ -186,11 +186,11 @@ static Expr * stripIndentation(const Pos & pos, SymbolTable & symbols, vector<Ex
     }
 
     /* Strip spaces from each line. */
-    vector<Expr *> * es2 = new vector<Expr *>;
+    std::vector<Expr *> * es2 = new std::vector<Expr *>;
     atStartOfLine = true;
     size_t curDropped = 0;
     size_t n = es.size();
-    for (vector<Expr *>::iterator i = es.begin(); i != es.end(); ++i, --n) {
+    for (std::vector<Expr *>::iterator i = es.begin(); i != es.end(); ++i, --n) {
         ExprIndStr * e = dynamic_cast<ExprIndStr *>(*i);
         if (!e) {
             atStartOfLine = false;
@@ -223,9 +223,10 @@ static Expr * stripIndentation(const Pos & pos, SymbolTable & symbols, vector<Ex
         /* Remove the last line if it is empty and consists only of
            spaces. */
         if (n == 1) {
-            string::size_type p = s2.find_last_of('\n');
-            if (p != string::npos && s2.find_first_not_of(' ', p + 1) == string::npos)
-                s2 = string(s2, 0, p + 1);
+            std::string::size_type p = s2.find_last_of('\n');
+            if (p != std::string::npos && s2.find_first_not_of(' ', p + 1) == std::string::npos) {
+                s2 = std::string(s2, 0, p + 1);
+            }
         }
 
         es2->push_back(new ExprString(symbols.Create(s2)));
@@ -354,7 +355,7 @@ expr_op
   | expr_op UPDATE expr_op { $$ = new ExprOpUpdate(CUR_POS, $1, $3); }
   | expr_op '?' attrpath { $$ = new ExprOpHasAttr($1, *$3); }
   | expr_op '+' expr_op
-    { $$ = new ExprConcatStrings(CUR_POS, false, new vector<Expr *>({$1, $3})); }
+    { $$ = new ExprConcatStrings(CUR_POS, false, new std::vector<Expr *>({$1, $3})); }
   | expr_op '-' expr_op { $$ = new ExprApp(CUR_POS, new ExprApp(new ExprVar(data->symbols.Create("__sub")), $1), $3); }
   | expr_op '*' expr_op { $$ = new ExprApp(CUR_POS, new ExprApp(new ExprVar(data->symbols.Create("__mul")), $1), $3); }
   | expr_op '/' expr_op { $$ = new ExprApp(CUR_POS, new ExprApp(new ExprVar(data->symbols.Create("__div")), $1), $3); }
@@ -394,7 +395,7 @@ expr_simple
       $$ = stripIndentation(CUR_POS, data->symbols, *$2);
   }
   | PATH { $$ = new ExprPath(absPath($1, data->basePath)); }
-  | HPATH { $$ = new ExprPath(getHome() + string{$1 + 1}); }
+  | HPATH { $$ = new ExprPath(getHome() + std::string{$1 + 1}); }
   | SPATH {
       std::string path($1 + 1, strlen($1) - 2);
       $$ = new ExprApp(CUR_POS,
@@ -424,9 +425,9 @@ string_parts
 string_parts_interpolated
   : string_parts_interpolated STR { $$ = $1; $1->push_back($2); }
   | string_parts_interpolated DOLLAR_CURLY expr '}' { $$ = $1; $1->push_back($3); }
-  | DOLLAR_CURLY expr '}' { $$ = new vector<Expr *>; $$->push_back($2); }
+  | DOLLAR_CURLY expr '}' { $$ = new std::vector<Expr *>; $$->push_back($2); }
   | STR DOLLAR_CURLY expr '}' {
-      $$ = new vector<Expr *>;
+      $$ = new std::vector<Expr *>;
       $$->push_back($1);
       $$->push_back($3);
     }
@@ -435,7 +436,7 @@ string_parts_interpolated
 ind_string_parts
   : ind_string_parts IND_STR { $$ = $1; $1->push_back($2); }
   | ind_string_parts DOLLAR_CURLY expr '}' { $$ = $1; $1->push_back($3); }
-  | { $$ = new vector<Expr *>; }
+  | { $$ = new std::vector<Expr *>; }
   ;
 
 binds
@@ -487,9 +488,9 @@ attrpath
       } else
           $$->push_back(AttrName($3));
     }
-  | attr { $$ = new vector<AttrName>; $$->push_back(AttrName(data->symbols.Create($1))); }
+  | attr { $$ = new std::vector<AttrName>; $$->push_back(AttrName(data->symbols.Create($1))); }
   | string_attr
-    { $$ = new vector<AttrName>;
+    { $$ = new std::vector<AttrName>;
       ExprString *str = dynamic_cast<ExprString *>($1);
       if (str) {
           $$->push_back(AttrName(str->s));
@@ -603,7 +604,7 @@ Expr * EvalState::parseExprFromFile(const Path & path, StaticEnv & staticEnv)
 
 Expr * EvalState::parseExprFromString(const std::string & s, const Path & basePath, StaticEnv & staticEnv)
 {
-    return parse(s.c_str(), "(string)", basePath, staticEnv);
+    return parse(s.c_str(), "(std::string)", basePath, staticEnv);
 }
 
 
@@ -625,11 +626,11 @@ void EvalState::addToSearchPath(const std::string & s)
     size_t pos = s.find('=');
     std::string prefix;
     Path path;
-    if (pos == string::npos) {
+    if (pos == std::string::npos) {
         path = s;
     } else {
-        prefix = string(s, 0, pos);
-        path = string(s, pos + 1);
+        prefix = std::string(s, 0, pos);
+        path = std::string(s, pos + 1);
     }
 
     searchPath.emplace_back(prefix, path);
@@ -653,7 +654,7 @@ Path EvalState::findFile(SearchPath & searchPath, const std::string & path, cons
             if (path.compare(0, s, i.first) != 0 ||
                 (path.size() > s && path[s] != '/'))
                 continue;
-            suffix = path.size() == s ? "" : "/" + string(path, s);
+            suffix = path.size() == s ? "" : "/" + std::string(path, s);
         }
         auto r = resolveSearchPathElem(i);
         if (!r.first) { continue; }
@@ -662,7 +663,7 @@ Path EvalState::findFile(SearchPath & searchPath, const std::string & path, cons
     }
     format f = format(
         "file '%1%' was not found in the Nix search path (add it using $NIX_PATH or -I)"
-        + string(pos ? ", at %2%" : ""));
+        + std::string(pos ? ", at %2%" : ""));
     f.exceptions(boost::io::all_error_bits ^ boost::io::too_many_args_bit);
     throw ThrownError(f % path % pos);
 }