1 files changed, 89 insertions, 0 deletions
diff --git a/asl/string_builder.hpp b/asl/string_builder.hpp
new file mode 100644
index 0000000..378ec48
--- /dev/null
+++ b/asl/string_builder.hpp
@@ -0,0 +1,89 @@
+#pragma once
+
+#include "asl/buffer.hpp"
+#include "asl/string.hpp"
+#include "asl/string_view.hpp"
+
+namespace asl
+{
+
+template<allocator Allocator = DefaultAllocator>
+class string_builder
+{
+    buffer<char, Allocator> m_buffer;
+
+public:
+    constexpr string_builder() requires default_constructible<Allocator> = default;
+    explicit constexpr string_builder(Allocator allocator) : m_buffer{ASL_MOVE(allocator)} {}
+
+    constexpr ~string_builder() = default;
+
+    constexpr string_builder(const string_builder&) requires copy_constructible<Allocator> = default;
+    constexpr string_builder(string_builder&&) = default;
+
+    constexpr string_builder& operator=(const string_builder&) requires copy_assignable<Allocator> = default;
+    constexpr string_builder& operator=(string_builder&&) = default;
+
+    constexpr string_view as_string_view() const
+    {
+        auto span = m_buffer.as_span();
+        return string_view{span.data(), span.size()};
+    }
+
+    void reset()
+    {
+        m_buffer.clear();
+    }
+
+    // @Todo(C++23) Deducing this
+
+    string_builder& push(string_view sv) &
+    {
+        isize_t old_size = m_buffer.size();
+        m_buffer.resize_zero(old_size + sv.size());
+        asl::memcpy(m_buffer.data() + old_size, sv.data(), sv.size());
+        return *this;
+    }
+
+    string_builder&& push(string_view sv) &&
+    {
+        isize_t old_size = m_buffer.size();
+        m_buffer.resize_zero(old_size + sv.size());
+        asl::memcpy(m_buffer.data() + old_size, sv.data(), sv.size());
+        return ASL_MOVE(*this);
+    }
+
+    string_builder& push(char c) &
+    {
+        m_buffer.push(c);
+        return *this;
+    }
+
+    string_builder&& push(char c) &&
+    {
+        m_buffer.push(c);
+        return ASL_MOVE(*this);
+    }
+
+    string<Allocator> finish() &&
+    {
+        return string<Allocator>{ASL_MOVE(m_buffer)};
+    }
+
+    template<allocator StringAllocator = Allocator>
+    string<StringAllocator> as_string()
+        requires default_constructible<StringAllocator>
+    {
+        return string<StringAllocator>{as_string_view()};
+    }
+
+    template<allocator StringAllocator = Allocator>
+    string<StringAllocator> as_string(Allocator allocator)
+    {
+        return string<StringAllocator>{as_string_view(), ASL_MOVE(allocator)};
+    }
+};
+
+string_builder() -> string_builder<>;
+
+} // namespace asl