Start work on formatting

8 files changed, 129 insertions, 2 deletions

diff --git a/asl/BUILD.bazel b/asl/BUILD.bazel
index 06e2a9f..5137c8f 100644
--- a/asl/BUILD.bazel
+++ b/asl/BUILD.bazel
@@ -3,6 +3,7 @@ cc_library(
     hdrs = [

         "annotations.hpp",

         "assert.hpp",

+        "format.hpp",

         "integers.hpp",

         "layout.hpp",

         "maybe_uninit.hpp",

@@ -11,6 +12,9 @@ cc_library(
         "option.hpp",

         "utility.hpp",

     ],

+    srcs = [

+        "format.cpp",

+    ],

     visibility = ["//visibility:public"],

 )

 

@@ -23,4 +27,11 @@ cc_library(
     deps = [

         ":asl",

     ],

-) for name in ["integers", "maybe_uninit", "meta", "option", "utility"]]

+) for name in [

+    "format",

+    "integers",

+    "maybe_uninit",

+    "meta",

+    "option",

+    "utility",

+]]

diff --git a/asl/format.cpp b/asl/format.cpp
new file mode 100644
index 0000000..890e532
--- /dev/null
+++ b/asl/format.cpp
@@ -0,0 +1,12 @@
+#include "asl/format.hpp"

+

+void asl::format_internals::format(

+    writer* writer,

+    const char* fmt,

+    const type_erased_arg* args,

+    int64_t arg_count)

+{

+    formatter f(writer);

+    

+    f.write("Hello", 5);

+}

diff --git a/asl/format.hpp b/asl/format.hpp
new file mode 100644
index 0000000..6cffd3a
--- /dev/null
+++ b/asl/format.hpp
@@ -0,0 +1,84 @@
+#pragma once

+

+#include "asl/integers.hpp"
+#include "asl/meta.hpp"

+#include "asl/utility.hpp"

+

+namespace asl

+{

+

+// @Todo Move this to io

+class writer

+{

+public:

+    writer() = default;

+    ASL_DELETE_COPY_MOVE(writer);

+    virtual ~writer() = default;

+    

+    // @Todo Use string view, or span of bytes?

+    virtual void write(const char* str, int64_t len) = 0;

+};

+

+class formatter;

+

+template<typename T>

+concept formattable = requires (formatter& f, const T& value)

+{

+    AslFormat(f, value);

+};

+

+namespace format_internals

+{

+

+struct type_erased_arg

+{

+    const void* data;

+    void (*fn)(formatter&, const void*);

+

+    template<formattable T>

+    static constexpr void erased_fn(formatter& f, const void* data)

+    {

+        AslFormat(f, *reinterpret_cast<const T*>(data));

+    }

+

+    template<formattable T>

+    explicit constexpr type_erased_arg(const T& arg)

+        : data{&arg}

+        , fn{erased_fn<T>}

+    {}

+};

+

+// @Todo Use span

+void format(writer*, const char* fmt, const type_erased_arg* args, int64_t arg_count);

+

+} // internals

+

+class formatter

+{

+    writer* m_writer;

+

+public:

+    explicit constexpr formatter(writer* writer)

+        : m_writer{writer}

+    {}

+

+    // @Todo Use string_view

+    constexpr void write(const char* s, int64_t len)

+    {

+        m_writer->write(s, len);

+    }

+};

+

+// @Todo Use string_view

+template<typename... Args>

+void format(writer* w, const char* fmt, const Args&... args)

+{

+    auto type_erased_args[] = {

+        format_internals::type_erased_arg(args)...

+    };

+

+    // @Todo Use array extent

+    format_internals::format(w, fmt, type_erased_args, types_count<Args...>);

+}

+

+} // namespace asl

diff --git a/asl/format_tests.cpp b/asl/format_tests.cpp
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/asl/format_tests.cpp
diff --git a/asl/meta.hpp b/asl/meta.hpp
index 931310f..7372c3f 100644
--- a/asl/meta.hpp
+++ b/asl/meta.hpp
@@ -1,11 +1,15 @@
 #pragma once

 

+#include "asl/integers.hpp"

+

 namespace asl {

 

 struct empty {};

 

 template<typename T> struct id { using type = T; };

 

+template<typename... Args> static constexpr int64_t types_count = sizeof...(Args);

+

 template<typename T, T kValue> struct integral_constant { static constexpr T value = kValue; };

 template<bool B> using bool_constant = integral_constant<bool, B>;

 

diff --git a/asl/meta_tests.cpp b/asl/meta_tests.cpp
index 8456f92..e53f870 100644
--- a/asl/meta_tests.cpp
+++ b/asl/meta_tests.cpp
@@ -158,4 +158,9 @@ static_assert(asl::is_same<int, asl::un_ref_t<int&>>);
 static_assert(asl::is_same<int, asl::un_ref_t<int&&>>);

 static_assert(asl::is_same<int() &, asl::un_ref_t<int() &>>);

 

+static_assert(asl::types_count<int, float> == 2);

+static_assert(asl::types_count<int, int> == 2);

+static_assert(asl::types_count<int> == 1);

+static_assert(asl::types_count<> == 0);

+

 int main() { return 0; }

diff --git a/asl/option.hpp b/asl/option.hpp
index 8662250..7600252 100644
--- a/asl/option.hpp
+++ b/asl/option.hpp
@@ -116,7 +116,6 @@ public:
             m_has_value = false;

         }

     }

-    

 };

 

 } // namespace asl

diff --git a/asl/utility.hpp b/asl/utility.hpp
index 6cbff8e..2cbf8db 100644
--- a/asl/utility.hpp
+++ b/asl/utility.hpp
@@ -17,4 +17,16 @@ T exchange(T& obj, U&& new_value)
     return old_value;

 }

 

+#define ASL_DELETE_COPY(T)                         \

+    T(const T&) = delete;                          \

+    T& operator=(const T&) = delete;

+

+#define ASL_DELETE_MOVE(T)                         \

+    T(T&&) = delete;                               \

+    T& operator=(T&&) = delete;

+

+#define ASL_DELETE_COPY_MOVE(T)                    \

+    ASL_DELETE_COPY(T)                             \

+    ASL_DELETE_MOVE(T)

+

 } // namespace asl