Make ArgVisitor public and document it

Also remove unnecessary namespace qualification.

cppformat/format.cc

@@ -129,7 +129,7 @@ struct IntChecker<true> {
 
 const char RESET_COLOR[] = "\x1b[0m";
 
-typedef void (*FormatFunc)(fmt::Writer &, int, fmt::StringRef);
+typedef void (*FormatFunc)(Writer &, int, StringRef);
 
 // Portable thread-safe version of strerror.
 // Sets buffer to point to a string describing the error code.
@@ -169,7 +169,7 @@ int safe_strerror(
     }
 
     // Handle the case when strerror_r is not available.
-    int handle(fmt::internal::Null<>) {
+    int handle(internal::Null<>) {
       return fallback(strerror_s(buffer_, buffer_size_, error_code_));
     }
 
@@ -181,7 +181,7 @@ int safe_strerror(
     }
 
     // Fallback to strerror if strerror_r and strerror_s are not available.
-    int fallback(fmt::internal::Null<>) {
+    int fallback(internal::Null<>) {
       errno = 0;
       buffer_ = strerror(error_code_);
       return errno;
@@ -199,8 +199,8 @@ int safe_strerror(
   return StrError(error_code, buffer, buffer_size).run();
 }
 
-void format_error_code(fmt::Writer &out, int error_code,
+void format_error_code(Writer &out, int error_code,
-                       fmt::StringRef message) FMT_NOEXCEPT {
+                       StringRef message) FMT_NOEXCEPT {
   // Report error code making sure that the output fits into
   // INLINE_BUFFER_SIZE to avoid dynamic memory allocation and potential
   // bad_alloc.
@@ -209,22 +209,22 @@ void format_error_code(fmt::Writer &out, int error_code,
   static const char ERROR_STR[] = "error ";
   // Subtract 2 to account for terminating null characters in SEP and ERROR_STR.
   std::size_t error_code_size = sizeof(SEP) + sizeof(ERROR_STR) - 2;
-  typedef fmt::internal::IntTraits<int>::MainType MainType;
+  typedef internal::IntTraits<int>::MainType MainType;
   MainType abs_value = static_cast<MainType>(error_code);
   if (internal::is_negative(error_code)) {
     abs_value = 0 - abs_value;
     ++error_code_size;
   }
-  error_code_size += fmt::internal::count_digits(abs_value);
+  error_code_size += internal::count_digits(abs_value);
-  if (message.size() <= fmt::internal::INLINE_BUFFER_SIZE - error_code_size)
+  if (message.size() <= internal::INLINE_BUFFER_SIZE - error_code_size)
     out << message << SEP;
   out << ERROR_STR << error_code;
-  assert(out.size() <= fmt::internal::INLINE_BUFFER_SIZE);
+  assert(out.size() <= internal::INLINE_BUFFER_SIZE);
 }
 
-void report_error(FormatFunc func,
+void report_error(FormatFunc func, int error_code,
-    int error_code, fmt::StringRef message) FMT_NOEXCEPT {
+                  StringRef message) FMT_NOEXCEPT {
-  fmt::MemoryWriter full_message;
+  MemoryWriter full_message;
   func(full_message, error_code, message);
   // Use Writer::data instead of Writer::c_str to avoid potential memory
   // allocation.
@@ -233,7 +233,7 @@ void report_error(FormatFunc func,
 }
 
 // IsZeroInt::visit(arg) returns true iff arg is a zero integer.
-class IsZeroInt : public fmt::internal::ArgVisitor<IsZeroInt, bool> {
+class IsZeroInt : public ArgVisitor<IsZeroInt, bool> {
  public:
   template <typename T>
   bool visit_any_int(T value) { return value == 0; }
@@ -241,44 +241,43 @@ class IsZeroInt : public fmt::internal::ArgVisitor<IsZeroInt, bool> {
 
 // Checks if an argument is a valid printf width specifier and sets
 // left alignment if it is negative.
-class WidthHandler : public fmt::internal::ArgVisitor<WidthHandler, unsigned> {
+class WidthHandler : public ArgVisitor<WidthHandler, unsigned> {
  private:
-  fmt::FormatSpec &spec_;
+  FormatSpec &spec_;
 
   FMT_DISALLOW_COPY_AND_ASSIGN(WidthHandler);
 
  public:
-  explicit WidthHandler(fmt::FormatSpec &spec) : spec_(spec) {}
+  explicit WidthHandler(FormatSpec &spec) : spec_(spec) {}
 
   void report_unhandled_arg() {
-    FMT_THROW(fmt::FormatError("width is not integer"));
+    FMT_THROW(FormatError("width is not integer"));
   }
 
   template <typename T>
   unsigned visit_any_int(T value) {
-    typedef typename fmt::internal::IntTraits<T>::MainType UnsignedType;
+    typedef typename internal::IntTraits<T>::MainType UnsignedType;
     UnsignedType width = static_cast<UnsignedType>(value);
-    if (fmt::internal::is_negative(value)) {
+    if (internal::is_negative(value)) {
-      spec_.align_ = fmt::ALIGN_LEFT;
+      spec_.align_ = ALIGN_LEFT;
       width = 0 - width;
     }
     if (width > INT_MAX)
-      FMT_THROW(fmt::FormatError("number is too big"));
+      FMT_THROW(FormatError("number is too big"));
     return static_cast<unsigned>(width);
   }
 };
 
-class PrecisionHandler :
+class PrecisionHandler : public ArgVisitor<PrecisionHandler, int> {
-    public fmt::internal::ArgVisitor<PrecisionHandler, int> {
  public:
   void report_unhandled_arg() {
-    FMT_THROW(fmt::FormatError("precision is not integer"));
+    FMT_THROW(FormatError("precision is not integer"));
   }
 
   template <typename T>
   int visit_any_int(T value) {
     if (!IntChecker<std::numeric_limits<T>::is_signed>::fits_in_int(value))
-      FMT_THROW(fmt::FormatError("number is too big"));
+      FMT_THROW(FormatError("number is too big"));
     return static_cast<int>(value);
   }
 };
@@ -298,15 +297,15 @@ struct is_same<T, T> {
 // corresponding signed or unsigned type depending on the type specifier:
 // 'd' and 'i' - signed, other - unsigned)
 template <typename T = void>
-class ArgConverter : public fmt::internal::ArgVisitor<ArgConverter<T>, void> {
+class ArgConverter : public ArgVisitor<ArgConverter<T>, void> {
  private:
-  fmt::internal::Arg &arg_;
+  internal::Arg &arg_;
   wchar_t type_;
 
   FMT_DISALLOW_COPY_AND_ASSIGN(ArgConverter);
 
  public:
-  ArgConverter(fmt::internal::Arg &arg, wchar_t type)
+  ArgConverter(internal::Arg &arg, wchar_t type)
     : arg_(arg), type_(type) {}
 
   void visit_bool(bool value) {
@@ -317,8 +316,8 @@ class ArgConverter : public fmt::internal::ArgVisitor<ArgConverter<T>, void> {
   template <typename U>
   void visit_any_int(U value) {
     bool is_signed = type_ == 'd' || type_ == 'i';
-    using fmt::internal::Arg;
+    using internal::Arg;
-    typedef typename fmt::internal::Conditional<
+    typedef typename internal::Conditional<
         is_same<T, void>::value, U, T>::type TargetType;
     if (sizeof(TargetType) <= sizeof(int)) {
       // Extra casts are used to silence warnings.
@@ -327,7 +326,7 @@ class ArgConverter : public fmt::internal::ArgVisitor<ArgConverter<T>, void> {
         arg_.int_value = static_cast<int>(static_cast<TargetType>(value));
       } else {
         arg_.type = Arg::UINT;
-        typedef typename fmt::internal::MakeUnsigned<TargetType>::Type Unsigned;
+        typedef typename internal::MakeUnsigned<TargetType>::Type Unsigned;
         arg_.uint_value = static_cast<unsigned>(static_cast<Unsigned>(value));
       }
     } else {
@@ -336,35 +335,35 @@ class ArgConverter : public fmt::internal::ArgVisitor<ArgConverter<T>, void> {
         // glibc's printf doesn't sign extend arguments of smaller types:
         //   std::printf("%lld", -42);  // prints "4294967254"
         // but we don't have to do the same because it's a UB.
-        arg_.long_long_value = static_cast<fmt::LongLong>(value);
+        arg_.long_long_value = static_cast<LongLong>(value);
       } else {
         arg_.type = Arg::ULONG_LONG;
         arg_.ulong_long_value =
-            static_cast<typename fmt::internal::MakeUnsigned<U>::Type>(value);
+            static_cast<typename internal::MakeUnsigned<U>::Type>(value);
       }
     }
   }
 };
 
 // Converts an integer argument to char for printf.
-class CharConverter : public fmt::internal::ArgVisitor<CharConverter, void> {
+class CharConverter : public ArgVisitor<CharConverter, void> {
  private:
-  fmt::internal::Arg &arg_;
+  internal::Arg &arg_;
 
   FMT_DISALLOW_COPY_AND_ASSIGN(CharConverter);
 
  public:
-  explicit CharConverter(fmt::internal::Arg &arg) : arg_(arg) {}
+  explicit CharConverter(internal::Arg &arg) : arg_(arg) {}
 
   template <typename T>
   void visit_any_int(T value) {
-    arg_.type = Arg::CHAR;
+    arg_.type = internal::Arg::CHAR;
     arg_.int_value = static_cast<char>(value);
   }
 };
 
 // Write the content of w to os.
-void write(std::ostream &os, fmt::Writer &w) {
+void write(std::ostream &os, Writer &w) {
   const char *data = w.data();
   typedef internal::MakeUnsigned<std::streamsize>::Type UnsignedStreamSize;
   UnsignedStreamSize size = w.size();

cppformat/format.h

@@ -1305,30 +1305,114 @@ struct NamedArg : Arg {
   : Arg(MakeArg< BasicFormatter<Char> >(value)), name(argname) {}
 };
 
+class RuntimeError : public std::runtime_error {
+ protected:
+  RuntimeError() : std::runtime_error("") {}
+};
+
+template <typename Char>
+class PrintfArgFormatter;
+
+template <typename Char>
+class ArgMap;
+}  // namespace internal
+
+/** An argument list. */
+class ArgList {
+ private:
+  // To reduce compiled code size per formatting function call, types of first
+  // MAX_PACKED_ARGS arguments are passed in the types_ field.
+  uint64_t types_;
+  union {
+    // If the number of arguments is less than MAX_PACKED_ARGS, the argument
+    // values are stored in values_, otherwise they are stored in args_.
+    // This is done to reduce compiled code size as storing larger objects
+    // may require more code (at least on x86-64) even if the same amount of
+    // data is actually copied to stack. It saves ~10% on the bloat test.
+    const internal::Value *values_;
+    const internal::Arg *args_;
+  };
+
+  internal::Arg::Type type(unsigned index) const {
+    unsigned shift = index * 4;
+    uint64_t mask = 0xf;
+    return static_cast<internal::Arg::Type>(
+          (types_ & (mask << shift)) >> shift);
+  }
+
+  template <typename Char>
+  friend class internal::ArgMap;
+
+ public:
+  // Maximum number of arguments with packed types.
+  enum { MAX_PACKED_ARGS = 16 };
+
+  ArgList() : types_(0) {}
+
+  ArgList(ULongLong types, const internal::Value *values)
+  : types_(types), values_(values) {}
+  ArgList(ULongLong types, const internal::Arg *args)
+  : types_(types), args_(args) {}
+
+  /** Returns the argument at specified index. */
+  internal::Arg operator[](unsigned index) const {
+    using internal::Arg;
+    Arg arg;
+    bool use_values = type(MAX_PACKED_ARGS - 1) == Arg::NONE;
+    if (index < MAX_PACKED_ARGS) {
+      Arg::Type arg_type = type(index);
+      internal::Value &val = arg;
+      if (arg_type != Arg::NONE)
+        val = use_values ? values_[index] : args_[index];
+      arg.type = arg_type;
+      return arg;
+    }
+    if (use_values) {
+      // The index is greater than the number of arguments that can be stored
+      // in values, so return a "none" argument.
+      arg.type = Arg::NONE;
+      return arg;
+    }
+    for (unsigned i = MAX_PACKED_ARGS; i <= index; ++i) {
+      if (args_[i].type == Arg::NONE)
+        return args_[i];
+    }
+    return args_[index];
+  }
+};
+
 #define FMT_DISPATCH(call) static_cast<Impl*>(this)->call
 
-// An argument visitor.
+/**
-// To use ArgVisitor define a subclass that implements some or all of the
+  \rst
-// visit methods with the same signatures as the methods in ArgVisitor,
+  An argument visitor.
-// for example, visit_int(int).
+  To use `~fmt::ArgVisitor` define a subclass that implements some or all of the
-// Pass the subclass as the Impl template parameter. Then calling
+  visit methods with the same signatures as the methods in `~fmt::ArgVisitor`,
-// ArgVisitor::visit for some argument will dispatch to a visit method
+  for example, `visit_int(int)`.
-// specific to the argument type. For example, if the argument type is
+  Pass the subclass as the *Impl* template parameter. Then calling
-// double then visit_double(double) method of a subclass will be called.
+  `~fmt::ArgVisitor::visit` for some argument will dispatch to a visit method
-// If the subclass doesn't contain a method with this signature, then
+  specific to the argument type. For example, if the argument type is
-// a corresponding method of ArgVisitor will be called.
+  ``double`` then `visit_double(double)` method of a subclass will be called.
-//
+  If the subclass doesn't contain a method with this signature, then
-// Example:
+  a corresponding method of `~fmt::ArgVisitor` will be called.
-//  class MyArgVisitor : public ArgVisitor<MyArgVisitor, void> {
+
-//   public:
+  **Example**::
-//    void visit_int(int value) { print("{}", value); }
+
-//    void visit_double(double value) { print("{}", value ); }
+    class MyArgVisitor : public fmt::ArgVisitor<MyArgVisitor, void> {
-//  };
+     public:
-//
+      void visit_int(int value) { fmt::print("{}", value); }
-// ArgVisitor uses the curiously recurring template pattern:
+      void visit_double(double value) { fmt::print("{}", value ); }
-// http://en.wikipedia.org/wiki/Curiously_recurring_template_pattern
+    };
+
+  `~fmt::ArgVisitor` uses the `curiously recurring template pattern
+  <http://en.wikipedia.org/wiki/Curiously_recurring_template_pattern>`_.
+  \endrst
+ */
 template <typename Impl, typename Result>
 class ArgVisitor {
+ private:
+  typedef internal::Arg Arg;
+
  public:
   void report_unhandled_arg() {}
 
@@ -1422,82 +1506,6 @@ class ArgVisitor {
   }
 };
 
-class RuntimeError : public std::runtime_error {
- protected:
-  RuntimeError() : std::runtime_error("") {}
-};
-
-template <typename Char>
-class PrintfArgFormatter;
-
-template <typename Char>
-class ArgMap;
-}  // namespace internal
-
-/** An argument list. */
-class ArgList {
- private:
-  // To reduce compiled code size per formatting function call, types of first
-  // MAX_PACKED_ARGS arguments are passed in the types_ field.
-  uint64_t types_;
-  union {
-    // If the number of arguments is less than MAX_PACKED_ARGS, the argument
-    // values are stored in values_, otherwise they are stored in args_.
-    // This is done to reduce compiled code size as storing larger objects
-    // may require more code (at least on x86-64) even if the same amount of
-    // data is actually copied to stack. It saves ~10% on the bloat test.
-    const internal::Value *values_;
-    const internal::Arg *args_;
-  };
-
-  internal::Arg::Type type(unsigned index) const {
-    unsigned shift = index * 4;
-    uint64_t mask = 0xf;
-    return static_cast<internal::Arg::Type>(
-          (types_ & (mask << shift)) >> shift);
-  }
-
-  template <typename Char>
-  friend class internal::ArgMap;
-
- public:
-  // Maximum number of arguments with packed types.
-  enum { MAX_PACKED_ARGS = 16 };
-
-  ArgList() : types_(0) {}
-
-  ArgList(ULongLong types, const internal::Value *values)
-  : types_(types), values_(values) {}
-  ArgList(ULongLong types, const internal::Arg *args)
-  : types_(types), args_(args) {}
-
-  /** Returns the argument at specified index. */
-  internal::Arg operator[](unsigned index) const {
-    using internal::Arg;
-    Arg arg;
-    bool use_values = type(MAX_PACKED_ARGS - 1) == Arg::NONE;
-    if (index < MAX_PACKED_ARGS) {
-      Arg::Type arg_type = type(index);
-      internal::Value &val = arg;
-      if (arg_type != Arg::NONE)
-        val = use_values ? values_[index] : args_[index];
-      arg.type = arg_type;
-      return arg;
-    }
-    if (use_values) {
-      // The index is greater than the number of arguments that can be stored
-      // in values, so return a "none" argument.
-      arg.type = Arg::NONE;
-      return arg;
-    }
-    for (unsigned i = MAX_PACKED_ARGS; i <= index; ++i) {
-      if (args_[i].type == Arg::NONE)
-        return args_[i];
-    }
-    return args_[index];
-  }
-};
-
 enum Alignment {
   ALIGN_DEFAULT, ALIGN_LEFT, ALIGN_RIGHT, ALIGN_CENTER, ALIGN_NUMERIC
 };
@@ -1911,9 +1919,9 @@ class PrintfFormatter : private FormatterBase {
 /**
   \rst
   An argument formatter.
-  To use `~fmt::BasicArgFormatter` define a subclass that implements some or all
+  To use `~fmt::BasicArgFormatter` define a subclass that implements some or
-  of the visit methods with the same signatures as the methods in `ArgVisitor`,
+  all of the visit methods with the same signatures as the methods in
-  for example, `visit_int(int)`.
+  `~fmt::ArgVisitor`, for example, `visit_int(int)`.
   Pass the subclass as the *Impl* template parameter. When a formatting
   function processes an argument, it will dispatch to a visit method
   specific to the argument type. For example, if the argument type is

doc/api.rst

@@ -42,6 +42,9 @@ arguments in the resulting string.
 Argument formatters
 -------------------
 
+.. doxygenclass:: fmt::ArgVisitor
+   :members:
+
 .. doxygenclass:: fmt::BasicArgFormatter
    :members:
 

test/util-test.cc

@@ -603,7 +603,7 @@ struct Result {
   Result(const wchar_t *s) : arg(make_arg<wchar_t>(s)) {}
 };
 
-struct TestVisitor : fmt::internal::ArgVisitor<TestVisitor, Result> {
+struct TestVisitor : fmt::ArgVisitor<TestVisitor, Result> {
   Result visit_int(int value) { return value; }
   Result visit_uint(unsigned value) { return value; }
   Result visit_long_long(fmt::LongLong value) { return value; }
@@ -612,10 +612,14 @@ struct TestVisitor : fmt::internal::ArgVisitor<TestVisitor, Result> {
   Result visit_long_double(long double value) { return value; }
   Result visit_char(int value) { return static_cast<char>(value); }
   Result visit_cstring(const char *s) { return s; }
-  Result visit_string(Arg::StringValue<char> s) { return s.value; }
+  Result visit_string(fmt::internal::Arg::StringValue<char> s) {
-  Result visit_wstring(Arg::StringValue<wchar_t> s) { return s.value; }
+    return s.value;
+  }
+  Result visit_wstring(fmt::internal::Arg::StringValue<wchar_t> s) {
+    return s.value;
+  }
   Result visit_pointer(const void *p) { return p; }
-  Result visit_custom(Arg::CustomValue c) {
+  Result visit_custom(fmt::internal::Arg::CustomValue c) {
     return *static_cast<const ::Test*>(c.value);
   }
 };
@@ -652,7 +656,7 @@ TEST(ArgVisitorTest, VisitAll) {
   EXPECT_EQ(&t, result.arg.custom.value);
 }
 
-struct TestAnyVisitor : fmt::internal::ArgVisitor<TestAnyVisitor, Result> {
+struct TestAnyVisitor : fmt::ArgVisitor<TestAnyVisitor, Result> {
   template <typename T>
   Result visit_any_int(T value) { return value; }
 
@@ -677,7 +681,7 @@ TEST(ArgVisitorTest, VisitAny) {
 }
 
 struct TestUnhandledVisitor :
-    fmt::internal::ArgVisitor<TestUnhandledVisitor, const char *> {
+    fmt::ArgVisitor<TestUnhandledVisitor, const char *> {
   const char *visit_unhandled_arg() { return "test"; }
 };